Oxides and oxygen-containing chlorine acids. Chlorine oxygen compounds

Lecture 3. Oxygen compounds halogen

Halogen oxides.

The use of halogens and their connections.

1. Galogen oxides

Halogens form a number of compounds with oxygen. But these compounds are unstable, ΔG O\u003e 0, they easily explode when heated and in the presence of organic compounds. They are obtained only indirectly.

Regarding resistant, the following oxygen compounds of halogen:

CL 2 O 3, BR 2 O 3, BRO 2, BR 2 O 5, I 2 O 4, I 2 O 6 are also known.

Getting.

Of 2 (fluorine oxide, or more correctly - oxygen fluoride) is the strongest oxidizing agent. It is obtained by action 2 on a chilled diluted alkali solution:

Chlorine and iodine oxides can be obtained by reactions:

Chemical properties:

Termically unstable:

All compounds of oxygen halogens (except 2) are acidic oxides.

CL 2 O, CL 2 O 7, I 2 O 5 when acid interacts with water:

CLO 2, CL 2 O 6 (C.O. \u003d + 4, +6 - unstable) When interacting with water, disproportionate:

Halogen oxides - Oxidifiers:

Of 2 contains +2 - very strong oxidizer:

Oxides from an intermediate degree of halogen oxidation disproportionate:

Oxygen-containing acids halogen

All oxygen-containing acids of halogen are well soluble in water. HCLO 4, HIO 3 IH 5 IO 6 are known in free form, the rest of the unstable, exist only in dilute aqueous solutions. The most stable compounds in S.O. -1 and +5.

Comparison of the strength of the acids

Chlorine oxygen acid structure:

Changing properties in a row of chlorine oxygen acids can be shown by the scheme:

This pattern is characteristic not only for chlorine, but also for bromine and iodine.

As an increase in the degree of oxidation of halogen, the charge of the ion increases, it enhances the attraction of it to O 2, and it makes it difficult to dissociation by the type of base. At the same time, the repulsion of the positive ionh + and e n + increases, it facilitates the dissociation by the type of acid.

Fig. 1. Fragment of the fragment of the Molecule E (OH) N

HOCL- amphoteric compound: may be dissociated by type of acid, and by the type of base:

In a row of CLO - -CLO 2 - -CLO 3 - -CLO 4 - the resistance of acids and anions increases. This is due to an increase in the number of electrons participating in the formation of relations:

Multiplicity of communication \u003d 1 Multiplicity of communication \u003d 1.5

d (CL - O) \u003d 0.170 nm D (CL - O) \u003d 0.145 nm

With an increase in the amount of oxygen atoms in acids, clocking Clock increases, so the oxidative capacity of the float.

Thus, in the row of HCLO → HCLO 2 → HCLO 3 → HCLO 4

acids increases;

the resistance of acids increases;

oxidative ability decreases.

The strength of oxygen-containing acids in a row of HOCL-HOBR-HOIMENSES due to the increase in the covalent radius and mild of communication - HAL:

K d 5 ∙ 10 -8 2 ∙ 10 -9 2 ∙ 10 -10

Oxidative properties decrease

In a row of HCO-HBRO-HOVELLES the resistance of acids. For example, when heated or the action of light, they decompose:

, Δg O (CJ) HCLO, HBRO, HIO

Getting.

Fluorinological acid is obtained using reactions:

. (with n.) !!!

Chlorinic acid is obtained by hydrolysis of chlorine (nsludal by the action of CaO 3):

Equilibrium is established when 30% chlorine will react.

HCLoIhBROPROPOW decomposition of hypochlorites and hypobromitis:

2. HCLO 2 is obtained from salts:

3. Hhalo 3 gets:

From salts:

Halogen oxidation with strong oxidizing agents:

4. HCLO 4, H 5 IO 6 of salts:

Chemical properties

Decompose when heated and in the light:

Strong oxidizers (all acids - stronger oxidizers than their salts):

Chlorine acid - weak oxidant only in concentrated solutions:

Salts oxokislot more resistant than acids. Their stability grows with an increase in the degree of oxidation.

Chemical properties of salts:

1. Chlorates and perchlorates disintegrated only when heated:

2. They, as well as acids, are oxidizing agents (but more weak than their acids):

Obtaining salts:

MehaloProduce the transmission of halidegains through a cold alkali solution, soda, potash:

Mehalo 3 is obtained by passing halogen through hot (60-70 o C) alkalis solutions:

Meclo 4 and IM 5 IO 6 oxidation of chlorates and heodatas in electrolysis or weak heating:

7. Application

Fluorine

Plastic acid is used to etch the glass, removing sand residues with metal casting, in chemical synthesis.

UF 6 is used in the nuclear industry.

CF 2 Cl 2 is used as refrigerants.

In metallurgy usecaf 2.

Fluoro-produced ethylene tetrafluoroethylene as a result of polymerization gives a valuable polymer - teflon, resistant to chemical reagents and indispensable in the manufacture of substances of particular purity, for the manufacture of instruments.

Fluorowork materials - in medicine, substitutes of blood vessels and heart valves. Products from fluoroplasties are widely used in aviation, electrical, nuclear and other industries.

Chlorine

Chlorine is necessary for synthesis in organic and polymer synthesis. The method of chlorine metallurgy receives silicon and refractory non-ferrous metals (titanium, niobium, tantalum, etc.).

It is used as an oxidizing agent and for sterilizing drinking water.

Salonic acid and halides are used in metallurgical, textile and food industries.

HCl is applied as a bactericidal and bleaching agent. Atomic oxygen, released when dissolved, atomic oxygen discolores colors and kills microbes:

Zhawl Water.- this is a mixture of chloride and hypochlorite of potassium, it is obtained by the action of alkali on "chlorine water", it possesses whitening properties:

Bellest or chlorine lime - white powder with a sharp odor, is used as whitening and disinfectant:

Bromine

Used in organic synthesis.

In photographic files usedAgbr.

Bromine compounds are used for drug production.

I 2 is necessary for metallurgy, it is used as an antiseptic and disinfectant. The iodine replaces hydrogen atoms in microorganisms protein molecules, which leads to their death:

For woodworking used Ki.

The compounds of the iodine are used to produce drugs, in food additives (NAI), for synthesis and in chemical analysis (iodometry).

Chlorine

Fluorine

Main subgroup VII group

In the elements of the main subgroup, which are called "halogens", at an external electron level, having a general structure ... NS 2 P 5, does not reach one electron to a steady eight-electron level. The energy of an electron affinity is large enough and halogens are very active in relation to metals and nonmetallam. The reactions with hydrogen are growing rapidly, the resulting halogen breeds of dissolving in water give acids of which grows from top to bottom down the group. A fluorine that does not have a D-sugro shows in its compounds only the degree of oxidation -1, the remaining halogens can exhibit the degree of oxidation -1, +1, +3, +5, +7.

In nature, it is found in the form of CAF 2 - fluorite, KHF 2 - bifluoride. A simple substance F 2 in industry is obtained by electrolysis of the bifluoride melt. F 2 - yellowish gas gas with suffocating smell, extremely poisonous, chemically extremely active.

Chemical properties

1. Fluorine interacts with all simple substances, except helium, neon and argon:

3F 2 + Cl 2 \u003d 2Clf 3;

3F 2 + S \u003d SF 6;

5F 2 + 2p \u003d 2PF 5;

2. In the interaction of F 2 with alkalis, oxygen fluoride is formed (of 2):

2F 2 + 2NAOH \u003d 2NAF + OF 2 + H 2 O

Of 2 - colorless gas, the smell resembles ozone, strongly poisonous. This is the only compound where oxygen has a degree of oxidation +2.

3. Since the interaction F 2 + H 2 \u003d 2HF occurs with an explosion, hydrogen fluoride is obtained not by direct synthesis, but by reaction:

CAF 2 + H 2 SO 4 (concluding) \u003d Caso 4 + 2hf

HF - easily boiling liquid (T KIP. \u003d +20 O C), mixed with water in any ratios. A 40% HF solution in water is called a platform acid. Plastic acid - the acid of medium power. This substance is one of the most dangerous physiological influences: poisonous, when entering the skin, it causes long non-healing ulcers for a long time, destroys teeth. The organic is charred by efficient sulfuric acid.

In the solution of the molecule of the molecule, the molecuic acid is strongly associated due to hydrogen bonds. Dimmers are most durable, therefore it is correct to record the formula for the plating acid in the form of H 2 F 2. Numerous salts of this dimer (KHF 2, etc.) are known.

4. Practical value There is a reaction of the interaction of a platform acid with silicon oxide (it is included in the glass):

SiO 2 + 4HF \u003d SIF 4 + 2H 2 O

This reaction is based on the application of patterns and drawings on the glass.

Application. F 2 is used in the production of fluoroorganic compounds, such as fluoroplast (Teflon). Teflon - white dense polymer stable in all aggressive environments Up to +350 o C. Fluorus gives high elasticity of rubber in the temperature range from -80 ° C to +200 o C.

In nature, it is found in the form of various compounds, the main of which is NaCl - the salt, the electrolysis of the aqueous solution of which chlorine is obtained on the anode. A simple substance CL 2 - yellow-green gas. At -34 o with easily liquefied. Poisonous. Easy to soluble in water.

Chemical properties

1. Chlorine has a slightly less affinity for an electron than fluorine, but remains very active non-metal. Many reactions involving Cl 2 go with an explosion. Cl 2 is a strong oxidizing agent. Does not react with oxygen, carbon, nitrogen. Reacts with complex molecules:

2no + Cl 2 \u003d 2nocl - nitrosyl chloride;

Co + Cl 2 \u003d COCL 2 - phosgene;

The chlorination of methane in industry is obtained by the following compounds:

CH 4 + CL 2 \u003d CH 3 CL - methyl chloride

CH 3 CL + CL 2 \u003d CH 2 Cl 2 - methylene chloride

CH 2 Cl 2 + Cl 2 \u003d CHCl 3 - chloroform

CHCL 3 + CL 2 \u003d CCL 4 - carbon four-chloride

2. Hydrogen chloride can be obtained by direct synthesis of simple substances:

Cl 2 + H 2 \u003d 2HCl

this reaction refers to the photochemical, i.e. coming under the action of light.

In the laboratory conditions, hydrogen chloride is usually obtained from NaCl when heated with concentrated sulfuric acid:

NaCl + H 2 SO 4 (concludes) \u003d NaHSO 4 + HCl

Hydrogen chloride is a sharp smell gas, well-soluble in water to form hydrochloric acid (solubility limit of 38%). Salonic acid is stronger than the packing, not poisonous. In concentrated state is a reducing agent:

K 2 Cr 2 O 7 + 14hCl (concluding) \u003d 2KCl + 2CrCl 3 + 3Cl 2 + 7H 2 O

HCLO - chlorothic acid. It corresponds to acid oxide CL 2 O. Soli are called hypochlorites.

HCLO 2 - chloride acid. Acid oxide CL 2 O 3 is not received. Salts are chlorite.

HCLO 3 - Chlornic acid. Acid oxide CL 2 O 5 is not received. Salts - chlorates.

HCLO 4 - chlorine acid. Acid oxide - Cl 2 O 7. Salts are perchlorates.

1) HCLO is a yellowish liquid. There is only solutions. It turns out when the chlorine interacts with water (without heating):

Cl 2 + H 2 O \u003d HCl + HCLO

Salts of this acid are obtained under the action of chlorine alkali:

2KOH + CL 2 \u003d KCLO + KCl + H 2 O

used as a bleach in the textile industry.

2) HCLO 2, HCLO 3 - do not have anhydrides (acid oxides). Salts of these acids are used in pyrotechnics and explosive work. The greatest value It has KCLO 3. – Potassium chlorate (beverage salt), obtained by the saturation of hot alkali chlorine:

3CL 2 + 6KOH \u003d KCLO 3 + 5KCl + 3H 2 O

Chlorates are the strongest oxidants. When hit or heated explodes.

3) KLO 2 is known, which can be obtained by reaction:

2KCLO 3 + H 2 C 2 O 4 \u003d K 2 CO 3 + CO 2 + H 2 O + 2CLO 2

CLO 2 - green-yellow gas, when dissolved in water gives a mixture of acids:

2CLO 2 + H 2 O \u003d HCLO 2 + HCLO 3

4) Careful heating chlorates can be transferred to perchlorates from which chlorine acid can be obtained:

KCLO 4 + H 2 SO 4 \u003d HCLO 4 + KHSO 4

Hlornic acid HCLO 4 – Mobile fluid, very explosive, the strongest of all known acids. Almost all of its salts are well soluble in water.

5) In a row of HCLO - HCLO 2 - HCLO 3 - HCLO 4, the strength of the acids grows, and the oxidative ability drops.

Chlorine is widely used in the chemical industry to obtain hydrogen chloride and hydrochloric acid, chlorine synthesis organic substancesDisinfection of drinking water, in the textile industry for whitening fabrics, in the production of pesticides.

PHYSIOCHEMICAL PROPERTIES

Chlorine forms a series of oxygen acids - a chloronous NSU, NSU2 chloride, chloropy NS! 03 and chlorine NS In the equation of the dependence of the concentration of chlorine dioxide in the solution from (in mol / l) from the partial pressure P (in mm RT. Art.) With = Kr At 0, 5, 10, 25 and 35 °, respectively, equal: 70.6, 56.3, 46.2, 30.2 and 21.5. With increasing temperature, the solubility of chlorine dioxide in water is sharply reduced. The solubility of SUN in other solvents (SS14, H2SO4 and SNZSON) is also subject to the law of Henry34. In aqueous solutions on cold, chlorine dioxide decomposes extremely slowly, in hot water decomposes with the formation of HCIO3, Ci2 and og. The existence of crystallohydrate C102 6N2035 has been established.

It is assumed that chlorine dioxide is anhydride36, forming with water appropriate acid H2CIO3 and H2CI2O5, is very unstable and renovated by metals to NSYUG - in the absence of reducing agents, the rate of decomposition of these acids above the speed of their formation. With hydrogen peroxide, chlorine dioxide reacts, forming a chloride acid37: 2Sy2 + H202 \u003d 2NC102 + 02

Chlorine dioxide annoys the respiratory tract and causes a fish pain already when diluted 45: 1 000 000.

Chloride acid 38-40 is highlighted in free form, but is usually obtained in aqueous solutions. The constant of dissociation is equal to 1.07-Yu-2 at 18 °. The formation of chloride acid occurs in significant quantities only in a strong-acid medium (pH<3). При этом в растворе наряду с хлористой кислотой нахо­дится и двуокись хлора 4I.

Chlorite - salts of chloride acid in a solid state under normal conditions are quite stable connections. Sour aqueous solutions decompose the faster than the higher the temperature and less pH. Sufficiently stable alkaline solutions42. Some chlorites can be obtained by the effect of free chloride acid on insoluble carbonates43. Sodium chlorite crystallizes from an alkaline solution in the form of anhydrous NAC102 salt and trihydrate NAC102-3H20, turning into anhydrous salt at 37.4 ° 44. When heated to 175 ° decomposes with oxygen release. The reaction comes at high speed up to the explosion. In weakly alkaline solutions containing no more than 1 Mr. / l NAC102, chlorite sodium does not decompose when boiling. In more concentrated solutions, it decomposes on the reactions of 45.46:

3 NaCl02 = 2 NaClc.>3 + NaClNAC102 - NaCl+ 02

The rate constants of these reactions are47, respectively, at 103 °: 0.65-7 and 6 and 1.2-10 "7; at 83 °: 1.6-10 ~ 7 and 0.2-10" 8.

Chlorinated acid in free form may exist only in solution. It is a strong acid and an energetic oxidizing agent. Its salts - chlorates - mostly well soluble in water; In solutions are not oxidants.

Potassium chlorat or bertolet Salt KSHSUM crystallizes in anhydrous form in the form of transparent colorless monoclinic crystals with a density of 2.32 g / cm3. The solubility of the KS103 in water: at 0 ° - 3.21%, at 104 ° (boiling point) -37.6%. When heated to 368.4 °, the KSIsystem melts, and then begins to decompose by reactions:

2xusive \u003d 2x1 +302 +23.6 to Cal.4x103 \u003d zxu4 + ks1 + 70.9 kkal

The products formed (KS1 and KS104) accelerate48 oxygen release. At 610 °, the perchlorate of potassium is melted and decomposed:

KSY4 \u003d KS1 + 202 - 7.9 kkal

In the presence of catalysts (MP02, etc.), potassium chlorate decomposes at lower temperatures with intense oxygen release. Potassium chlorate in an acidic environment is a strong oxidizing agent. The mixture of it with coal, gray and other substances explode from the blow. Potassium chlorate (and other chlorates) poisonous (fatal dose - 2-zg KSJ3).

Sodium chlorate NAC103 crystallizes in anhydrous form, highly hygroscopic, is blown in the air. A saturated aqueous solution contains at -15 ° 41.9%, at 122 ° 74.1% NAC103. The melting point of sodium chlorate is in the range of 248-264 °. Cases of sodium chlorate explosions in warehouses during storage, as well as the signage of the dry parts of the plants, to which Sodium chlorat got. In the presence of hygroscopic substances (sassy, \u200b\u200bMgCl2 et al.) 4a, as well as polyborators or meta-borates sodium explosive - and sodium chlorate flashes decreases. In the NAC103-NAC102-H20 50 system in the temperature range of 15-45 °, anhydrous NAC103 and NaCl02, as well as NAC102-3H20, crystallizes.

Calcium calcium chlorate (sv) 2 crystallizes from aqueous solution in the form of dihydrate51, melting at 130 °. A saturated aqueous solution is boiling at 182 °. Anhydrous calcium chlorate decomposes when heated to 334 °.

MG (C103) 2 6H20 chlorine hexagidate is rhombic crystals - long needles or leaves. At 35 ° partially melts and goes into tetrahydrate. Its solubility in water is 53% at 0 °, 56.5% at 18 °, 60.23% at 29 ° and 63.65% at 35 °. It is distinguished by high hygroscopicity, does not explode and safely in fire ratio49.

Chlorine acid 52 forms two crystallohydrates - NS104 4N20 and NSU4 zn20 53 and is a strong electrolyte54 The coefficient of chloroic acid activity at 25 ° varies from 0.911 to 0.804 with a change in the concentration of NSU4 from 0.01 to 0.1 M. in 1 kg Radio®5.

Potassium perchlorate KSU4 forms rhombic crystals with a density of 2.52 g / cm3. At 0 at 100 ml Water dissolves 0.75 g and at 100 ° - 21.8 g KSY4. Pure potassium perchlorate decomposes at 537-600 ° at KS1 and 02. COP103 is formed as an intermediate product, which melted, accelerates decomposition 56. The reaction is accelerated in the presence of KS1, KBR, Ki57, C, FE, CO, MGO, etc.58.

Magnesium perchlorate forms crystal hydrates with 2, 4 and 6 water molecules. Equilibrium steam pressure at 23 ° over Mg (C104) 2 6N20 is 20.9 mm RT. Art., Over MG (C104) 2 4N20- 8,15 mm RT. Art., And over MG (C104) 2-2h20 near Yu-4-sh-5 MM. RT. Art. 17e.When heated above 400 ° Mg (C104) 2 decomposes.

Ammonium perchlorate is characterized by the highest weight content of oxygen among all perchlorates. In 100 g at 0 ° dissolves 10.7 g at 85 ° - 42.5 G. NH4CIO4. In a mutual water system of perchlorates and chlorides. Ammonium and magnesium the least soluble salt at 25 ° is NH4CiO461.

Chlorine oxygen compounds higher degrees Oxidations - fire - and explosive, especially in the presence of impurities easily oxidizing, such as organic substances, from the contamination of which they should be protected. The explosion of solid dry chlorates and perchlorates can be caused by a blow or strong push, which must be taken into account when drying, grinding and transporting these in< ществ. Эти операции должны осуществляться в аппаратах, в ко­торых исключена возможность ударов металлических частей.

Application

Salts of lower oxygen acids chlorine are good whitening means due to their high oxidative activity. The main whitening and oxidative chlorine compound is chlorine lime62. Currently, hypochlorites, chlorites and chlorine dioxide are also widely used for these purposes.

The greatest amounts of chlorine lime are consumed in the textile and paper industry for bleaching tissues and cellulose (chlorine lime is often called herbal lime). Chlorine lime is used as an oxidizing agent in some chemical production (upon obtaining chloroform, chlorpicrin and other products), for disinfection of drinking and wastewater, for disinfection of vegetable stores63 and as a good degasser. It is also used to clean acetylene and some petroleum products.

Chlorine lime produced three brands (Table 112).

The loss of active chlorine in the chlorine lime of the brand A should be no more than 4% for 3 years of its storage from the date of shipment by the plant.

Chlorine lime brands B and in package in wooden barrels with a capacity from 50 to 275 l In fan-filled barrels or plywood drums with a capacity of 50 and 100 l and (for non-breaking storage) in dry fuel wooden barrels with a capacity from 50 to 250 l. Chlorine lime brand A, as well as brands B (for long-term storage) package in steel drums with a capacity of 100 l. Barrels or drums with chlorine lime are sealed and stored in a dry and cool room, protected from direct sunlight. Instead of wooden barrels and drums, polyethylene bags are also used.

Despite these precautions, chlorine lime during storage gradually loses active chlorine. With insufficient tightness of the container, some product samples almost completely lose active chlorine for one year, and sometimes much more. At 40-45 °, the ordinary chlorine lime completely loses activity for 2 months.

Chlorine lime is increasingly crowded with other more comfortable in use by bleaching and oxidative substances6-hypochlorites, chlorine dioxide, etc.

Sodium hypochlorite in the form of an aqueous solution is largely distributed due to the simplicity of manufacturing it at the point of consumption. It is a semi-product 64 in the production of hydrazine, plastic masses, synthetic fibers, etc. proposed 65 hypochlorite method of recycling of dust-like waste from sharpening a carbide tool based on oxidation of tungsten carbide in alkaline solutions NACIO and a tungsten transition into a solution.

According to GOST 11086-64, sodium hypochlorite must be a transparent greenish-yellow liquid without precipitation and suspended particles containing by the time the consumer will not less than 185 g / l active chlorine and no more than 0.07 g / l gland; NaOH content should be in the range of 10-20 g / l The sodium hypochlorite solution is stored and transported in closed humated or protected by viniplast tanks and containers at a temperature not higher than 25 °.

Technical calcium hypochlorite containing more than 50% of active chlorine, transportable than chlorine lime. With a hypo - calcium chlorite transported less than 100% ballast (impurities and containers), while with chlorine lime 250-300%. An important advantage of calcium hypochlorite, compared with chlorine lime, is the absence of a significant sediment in dissolving it in water66 (when the chlorine lime is dissolved, the precipitate of the main salts is formed, in which sometimes up to 50% of the active chlorine is lost). Proposed67 Use a mixture of 2 weight. h. sa (os1) 2 and 0.8 weight. h. Na2S04 in the form of water treatment tablets.

Calcium hypochlorite is produced in the form of a 2 2 2 2 2 2 2n20, denoted by DTSGK, and less often as a two-axis calcium hypochlorite Ca (C10) 2 2s (OH) 2, denoted by DSGK - GOST 13392-67 provides for the release of DTSGK

and the 2nd grade. They should be accordingly: active chlorine at least 55 and 50% and moisture not more than 1 and 1.5%; The content of the total chlorine should not exceed the half of the active chlorine (%) plus 6% for the 1st grade, or plus 7% for

DTSGK is packaged in galvanized drums. The product must be stored in a dry, unheated room.

Chlorine dioxide in their oxidizing properties occupies an intermediate place between chlorates and hypochlorites. The main advantage of her advantage as a bleaching reagent is that it almost does not actually act on the fiber fiber cell. Therefore, it is widely used asA better bleaching agent for wood (paper) mass and pulp, as well as for sterilization and deodorization of water68 and food products. Due to the difficulty of storage and transportation, SUN is usually obtained at the point of consumption and used in the form of a 10% mixture with air69.

Sodium chlorite is widely used in the textile industry for whitening fabrics, yarn, fiber. At the same time, high quality bleaching is achieved without reducing fiber strength. It is also used as the starting material to obtain small amounts of chlorine dioxide.

Potassium chlorate is mainly used in the match industry, in pyrotechnics, in small quantities in the pharmaceutical industry, as well as in explosive technique.

The composition of the technical beverage salt must correspond to the data of the table. 113.

Table 113.

The composition of technical bertolenova Sololi. (by GOST 2713-70)

Potassium chlorate (in terms of dry matter), notHer .....

Moisture, no more ................................................ .................................

Not soluble in water substances not more................................

Chlorides (in terms of SAS12), no more ..................................

Sulfates (in terms of CAS04), no more ................................

Bromat (in terms of KVG03), no more ...................................

Alkali (in terms of sao), no more .......................................

Organic substances, no more ............................................. ....

Heavy metals (in terms of ply), no more. . . . Iron (FE), not saline

Sodium chlorate is used as herbicide and defoliant (in limited quantities due to its hygroscopicity). It is mainly used as a semi-product for the production of other chlorates, potassium perchlorate, chlorine acid, chlorine dioxide and sodium chlorite. Some (small) amounts of sodium chlorate are used for cellulose white. The use of NAC103 for the manufacture of candles, which are the source of oxygen on nuclear submarines7070.

The composition of the technical chlorate of sodium, crystalline and mortar (or pulp), according to GOST 12257-66, must comply with the requirements given in Table. 114.

Table U4.

Composition of technical chlorate sodium (GOST 12257-66)

* In the recalculation of the IA 100% product.

Bertolet salt and sodium chlorate are packaged in bags] of a polyethylene or polyvinyl chloride film, nested steel galvanized or coated with perchlorvinyl lacquer drums, or in bags of chlorinic tissue (also with a film insert).

Calcium chlorate is a general-action herbicide and is widely used to destroy weeds.

Magnesium chlorate also serves as a herbicide and, in addition, is a defoliant applied to precomply remove cotton leaves 71\u003e 72, and in large doses it can serve as a siquant for precompanic drying of cotton and other plants.

Magnesium chlorate (defoliant), according to GOST 10483-66, must contain 60 ± 2% Mg (C103) 2 6N20 and not more than 0.6% of water dissoluable in water; The temperature of the beginning of its melting should be no less than 44 °. It is transported in hermetic drums from black roofing steel or in paper bituminous dubbed five-layer bags with a liner from a polyethylene or polyvinyl chloride film.

Perchlorates are used in the production of explosive and pyrotechnic materials52 "73. Suggested 74 mixtures containing ~ 60% KS104, forming a hygroscopic smoke to regulate precipitation.

Ammonion perchlorates, the ammonium perchlorate used for the manufacture of smokeless explosives75 "76 is of particular importance, heavy metal perchlorates and chloroic acid are used as electrolytes in galvanoplasty, during cementation, etc. In the presence of NS104, it is obtained on electrolyte-polished copper dense, shiny palladium precipitation77. Indicate 78 On the possibility of reextraction of rhenium with chlorine acid from organic solvents.

All chlorine oxides have a sharp smell, thermally and photochemically unstable, prone to explosive decay. +1 SL 2 O T. PL O. With T. Kip ° C -120, 6 +3 +4 +4 +5 +6 +7 SL 2 O 3 SL. O 2 CL 2 O 4 CL 2 O 5 CL 2 O 6 SL 2 O 7 is not received by NCl. O 2 -117 9, 7 2, 0 -59 was not received 44, 5 -93, 4 203 nsl. O 3 3 87 HCL. O 4 Chloronov Chlorine Typical Chlorinov Tairy is a strong very strong hypochlorite chlorates Na. Cl. O 2 ksl. O 3 perchlorates weak middle power Chlorine CCl. O 4.

§ All compounds with chlorine in positive degrees are very strong oxidizing agents. § The most strongly oxidative properties are expressed in chlorothic acid, although it is weak and unstable. § Free oxygen-containing chlorine acids are unstable and, except for chlorine acid, exist only in solution. All of them are strong oxidizing agents. § Power of acids and their oxidative properties of various concepts. § in a number of HCl. O - HCl. O 2 - HCl. O 3 - HCl. O 4 Resistance and acid strength grows, and reactivity decreases.

The ratio of halogens to water x 2 F 20 + 2 H 2 O- 2 → 4 HF + O 2 Interaction, F 2 - Oxidizer, Ü Cl 20 + H 2 O ↔ HCl + 1 O + HCl- 1 Interaction, CL 20 - Oxidizer , reducing agent; reaction - disproportionation, x BR 20 + H 2 O ↔ HBr +1 O + HBr - 1 is well soluble, the interaction is practically not occurring; BR 20 - oxidizing agent, reducing agent; Reaction - disproportionation, x i 2 + h 2 o ≠ badly soluble, the interaction practically does not occur; ü at 2 + h 2 o ≠ badly soluble, the interaction practically does not happen

Chlorine oxides Parameter Comparison of chlorine oxide (I) Chlorine (IV) State of aggregation with n. y , color drilling gas; at t °

Chlorine oxide comparison (I) chlorine oxide (IV) Chlorine oxide (VII) Thermal stability is thermally unstable thermal stability, decomposes into the light. The most stable chlorine oxide is slowly decomposed at room temperature, decomposes when heated to 120 ° C is heated toxic, affects the respiratory Ways toxic strongly poisonous toxic attitude towards water are well soluble, interact with water

Methods for obtaining chlorine oxides chlorine name, UHR chlorine oxide (I) The interaction of mercury oxide (II) with chlorine at 0 ° C: Hg. O (solid) + 2 Cl 2 (gas) → HG. CL 2 + CL 2 O chlorine oxide (IV) 1) Interaction of potassium chlorate with oxalic acid: KCL. O 3 + H 2 C 2 O 4 → K 2 CO 3 + 2 Cl. O 2 + CO 2 + H 2 O (laboratory method); 2) transmitting sulphous gas SO 2 into acidified sodium chlorate solution: 2 Na. Cl. O 3 + SO 2 + H 2 SO 4 \u003d 2 Na. HSO 4 + 2 Cl. O 2 (industrial method) Chlorine oxide (VI) Oxidation of chlorine oxide (IV) Ozone: 2 Cl. O 2 + 2 O 3 \u003d 2 O 2 + CL 2 O 6 Chlorine oxide (VII) The interaction of chlorine acid with phosphoric anhydride - phosphorus oxide (V): 8 HCl. O 4 + P 4 O 10 → 4 Cl 2 O 7 + 2 H 4 P 2 O 7

Chemical properties of chlorine oxides CL 2 O - chlorine oxide (i) CL 2 + 1 O + H 2 O \u003d 2 HCl + 1 O NOT ARP, CL 2 + 1 O + 2 KOH \u003d 2 KCL + 1 O + H 2 O OSR, Cl. O 2 - chlorine oxide (IV) 2 Cl + 4 O 2 + H 2 O \u003d HCl + 3 O 2 + HCl + 5 O 3 OPS, CL + 4 - and reducing agent, and oxidizing agent 2 CL + 4 O 2 + 2 KOH \u003d KCl + 3 O 2 + KCl + 5 O 3 + H 2 O ovr, CL + 4 - and reducing agent, and oxidizer CL 2 O 6 - chlorine oxide (VI) CL 2 + 6 O 6 + H 2 O \u003d HCl + 5 O 3 + HCl + 7 O 4 ORP, CL + 6 - and reducing agent, and oxidizing agent Cl 2 + 6 O 6 + 2 KOH \u003d KCl + 5 O 3 + KCl + 7 O 4 + H 2 O OVR, CL + 6 - Both the reducing agent, and the oxidizer CL 2 O 7 - chlorine oxide (VII) CL 2 + 7 O 7 + H 2 O \u003d 2 HCl + 7 O 4 is not OVR, and CL 2 + 7 O 7 + 2 KOH \u003d 2 KCl + 7 O 4 + H 2 O is not OVR,

Oxygen-containing acid chlorine Physical properties, methods for obtaining chemical properties- ratio to heating, alkalis solutions and main oxides

Oxygen-containing acid chlorine formula formula CL oxidation degree in NCl + 1 oh NCl + 3 O 2 HCl + 5 O 3 HCl + 7 O 4 +1 +3 +5 +7 increases thermal stability increases the acid increases very weak acid of weak acid partially dissociates in water the form of the existence of medium strength acid, closer to a strong one of the most strong acids dissociates almost irreversibly exist only in the solution is highlighted in free form

Chlornanotic acid is obtained by dissolving chlorine oxide (I) in water (1): (1) Cl 2 O + H 2 O → 2 HCl. O Chlorinic acid - chlorine water, chlorine solution in water. It is obtained in a chlorine in a chlorine into water to saturation (1 water volume dissolves at 20 ° C about 2, 2 volume of gaseous chlorine) (2): (2) Cl 2 + H 2 O ⇌ HCl. O + HCl generated HCl. O decomposes into the light on O 2 and HCl. Chlorine water is a strong oxidizing agent, it is used to disinfect water and bleaching tissues.

Chlorinous acid The acid solution is obtained from its salts - chlorites Ba (Cl. O 2) 2 + H 2 SO 4 → 2 HCl. O 2 + BA. SO 4 ↓ as well as reaction: 2 Cl. O 2 + H 2 O → NCl. O 2 + NCl. O 3 Chloride acid is an acid of medium power, closer to weak chlorite is used for bleaching.

Chlorinated acid of aqueous solutions at a concentration below 30% on cold is rather stable; In more concentrated solutions, disintegrates: in 8 HCl. O 3 \u003d 4 HCl. O 4 + 3 O 2 + 2 Cl 2 + 2 H 2 O. Chlornic acid - a strong oxidizing agent; Oxidative ability increases with an increase in concentration and temperature, for example, in 40% acid flames, filter paper. Chlorinous acid in laboratory conditions are obtained by interacting with barium chlorate with dilute sulfuric acid: Ba (Cl. O 3) 2 + H 2 SO 4 \u003d BA. SO 4 ↓ + 2 HCl. O 3.

Chlorine acid Anhydrous chlorine acid is obtained by interacting with sodium perchlorats or potassium with concentrated sulfuric acid or hydrochloric acid solutions with oleum, as well as when the chlorine oxide interaction (VII) with water: KCL. O 4 + H 2 SO 4 → KHSO 4 + HCl. O 4 Cl 2 O 7 + H 2 O → 2 NCl. O 4.

Thermal stability of acids - the ratio to the heating of chlorine acid (HCl. O 4) Ø is possible to be isolated in free form; Ø With moderate heating with phosphoric anhydride, § 2 HCl decomposes. O 4 + P 2 O 5 \u003d Cl 2 O 7 + 2 HPO 3 Chlornic acid (HCl. O 3) Ø With weak heating, § 8 HCl decomposes. O 3 \u003d 4 HCl. O 4 + 3 O 2 + 2 Cl 2 + 2 H 2 O Chloride Acid (HCl. O 2) Ø Very unstable, decomposed at room temperature in the light § 4 nsl. O 2 \u003d NCl + HCl. O 3 + 2 Cl. O 2 + H 2 O Chlornanotic acid (HCl. O) Ø 2 HCl. O \u003d 2 HCl + O 2 (under the action of light)

Attitude to solutions of alkali in the interaction of oxygen-containing chlorine acids with alkali solutions by the exchange reaction, salt of this acid and water is formed. Neutralization reaction occurs. HCl. O 2 + Na. OH \u003d Na. Cl. O 2 + H 2 O; HCl. O 3 + KOH \u003d KCL. O 3 + H 2 O; The ratio to the main oxides in the interaction of oxygen-containing chlorine acids with the main oxides for the exchange reaction is formed by salt of this acid and water. 2 HCl. O + Na 2 O \u003d 2 Na. Cl. O + H 2 O; 2 HCl. O 4 + Cu. O \u003d Cu (Cl. O 4) 2 + H 2 O

15.1. general characteristics halogens and chalcogen

Halogens ("born salts") - elements of the group VIIA. These include fluorine, chlorine, bromine and iodine. The same group includes an unstable, and therefore not occurring in nature ASTAT. Sometimes hydrogen is also attributed to this group.
Halcogens ("born copper") - elements of the group VIA. These include oxygen, sulfur, selenium, tellurium and practically not found in nature polonium.
Of eight atoms existing in nature elements These two groups are the most common oxygen atoms ( w. \u003d 49.5%), followed by the prevalence of chlorine atoms ( w. \u003d 0.19%), hereinafter - sulfur ( w. \u003d 0.048%), then - fluorine ( w. \u003d 0.028%). Atoms of the remaining elements hundreds and thousands of times less. Oxygen you have already studied in the eighth grade (ch. 10), chlorine and sulfur are the most important elements - you will get acquainted with them in this chapter.
The orbital radii atoms of halogen and chalcogenes are small and only the fourth atoms of each group are approaching one animavra. This leads to the fact that all these elements are elements that form non-metals and only tellurium and iodine show some signs of amphoterity.
General valence electronic formula halogen - nS. 2 nP. 5, and chalcogen - nS. 2 nP. four . The small sizes of atoms do not allow them to give electrons, on the contrary, the atoms of these elements are inclined to take them, forming one-charge (in halogen) and two-chain (at chalcogen) anions. Connecting with small atoms, the atoms of these elements form covalent bonds. Seven valence electrons provide the possibility of halogen atoms (except fluorine) to form up to seven covalent bonds, and six valence electrons of chalcogen atoms - up to six covalent bonds.
In fluorine compounds - the electronest element itself - only one degree of oxidation is possible, namely -i. At oxygen, as you know, the maximum degree of oxidation + II. At the atoms of the remaining elements, the highest degree of oxidation is equal to the number of the group.

Simple substances of the elements of the VIIA group of the same type in structure. They consist of diatomic molecules. Under normal conditions, fluorine and chlorine - gases, bromine - liquid, and iodine is a solid. By chemical properties These substances are strong oxidizers. Due to the growth of the sizes of atoms with an increase in the sequence number, their oxidizing activity is reduced.
Of the simple substances of the elements of the group VIA under normal conditions of gaseous conditions, only oxygen and ozone, consisting of diatomic and trochatomic molecules, respectively; The remaining solids. The sulfur consists of eightyatomic cyclic molecules S 8, selenium and tellurium of polymer molecules SE n. and te. n. . In its oxidative activity, halcogenies are inferior to halogens: only oxygen is a strong oxidizing agent, the rest exhibit oxidative properties to a much lesser extent.

Structure hydrogen compounds Halogens (NE) fully meets the overall rule, and halcogenies, in addition to conventional hydrogen compounds of the composition H 2 e, more complex hydrogen compounds of the composition H 2 n. chain structure. In aqueous solutions and halogen breeds, the remaining chalcogenic breeds exhibit acidic properties. Their molecules are particles-acids. Of these, only HCl, HBR and HI are strong acids.
For halogen education oxides Uncharacteristic, most of them are unstable, but the highest oxides of the composition of E 2 O 7 are known for all halogen (except fluorine, the oxygen compounds of which are not oxides). All halogen oxides are molecular substances, chemical properties - acid oxides.
In accordance with its valetal capabilities, halcogenies form two rows of oxides: EO 2 and EO 3. All these acidic oxides.

Hydroxides of halogen and chalcogenes are oxocoslotes.

Make abbreviated electronic formulas and energy diagrams of atoms of elements VIA and VIIIA groups. Indicate external and valence electrons.

Chlorine is the most common, and therefore the most important out of halogen.
IN earth Kore Chlorine occurs in the composition of minerals: Galita (stone salt) NaCl, Silvin KCl, KCL carnallite · MgCl 2 · 6H 2 O and many others. The main industrial method of producing is the electrolysis of sodium chlorides or potassium.

A simple chlorine substance is a greenish color gas with a caustic suffocating smell. At -101 ° C condensed into the yellow-green liquid. Chlorine is very poisonous, during the First World War I even tried to use as a combat poisoning substance.
Chlorine is one of the strongest oxidizing agents. It reacts with most simple substances (exception: noble gases, oxygen, nitrogen, graphite, diamond and some others). As a result, halides are formed:
Cl 2 + H 2 \u003d 2HCl (when heated or in light);
5Cl 2 + 2p \u003d 2pCl 5 (when burning in an excess of chlorine);
Cl 2 + 2NA \u003d 2NACL (at room temperature);
3Cl 2 + 2SB \u003d 2SBCl 3 (at room temperature);
3Cl 2 + 2Fe \u003d 2FeCl 3 (when heated).
In addition, chlorine can oxidize many complex substances, for example:
CL 2 + 2HR \u003d br 2 + 2hCl (in the gas phase and in solution);
Cl 2 + 2hi \u003d i 2 + 2hCl (in the gas phase and in solution);
Cl 2 + H 2 S \u003d 2HCl + S (in solution);
Cl 2 + 2KBr \u003d br 2 + 2kcl (in solution);
Cl 2 + 3H 2 O 2 \u003d 2HCl + 2H 2 O + O 2 (in concentrated solution);
CL 2 + CO \u003d CCL 2 O (in the gas phase);
Cl 2 + C 2 H 4 \u003d C 2 H 4 Cl 2 (in the gas phase).
In water, chlorine is partially dissolved (physically), and partially reversibly reacts with it (see § 11.4 V). With a cold solution of potassium hydroxide (and any other alkali), a similar reaction proceeds irreversibly:

Cl 2 + 2OH \u003d CL + CLO + H 2 O.

As a result, a solution of chloride and potassium hypochlorite is formed. In the case of a reaction with calcium hydroxide, a mixture of CaCl 2 and Ca (CLO) 2 is formed, called chlorine lime.

With hot concentrated alkalis solutions, the reaction proceeds otherwise:

3Cl 2 + 6OH \u003d 5Cl + CLO 3 + 3H 2 O.

In the event of a reaction with KOH, potassium chlorate, called the bertolen salt, is obtained.
Chlorine-garden is the only one hydrogen connectionchlorine. This colorless gas with a suffocating smell is well soluble in water (reacts with it, forming oxony and chloride ions (see § 11.4). Its solution is called hydrochloric or chloride acid. This is one of the most important chemical technology products, since Salonic acid is consumed in many industries. It has a great importance for a person, in particular, because it is contained in gastric juice, contributing to digestion of food.
The chloride was previously obtained in industry, burning chlorine in hydrogen. Currently, the need for hydrochloric acid It is almost completely satisfied due to the use of chloride products formed as a by-product during chlorination of various organic substances, such as methane:

CH 4 + CL 2 \u003d CH 3 + HCl

And the laboratory chloride is obtained from sodium chloride, processing it with concentrated sulfuric acid:
NaCl + H 2 SO 4 \u003d HCl + NaHSO 4 (at room temperature);
2NACL + 2H 2 SO 4 \u003d 2HCl + Na 2 S 2 O 7 + H 2 O (when heated).
Higher oxide Chlorine CL 2 O 7 is a colorless oily liquid, a molecular substance, acidic oxide. As a result of the reaction with water, hydrochloric acid HCLO 4 forms a single chlorine oxocus, existing as an individual substance; The remaining chlorine oxocuslots are known only in aqueous solutions. Information about these chlorine acids are shown in Table 35.

Table 35. Chlorine and salts

Most chlorides are soluble in water. The exception is AGCL, PBCl 2, TLCL and HG 2 Cl 2. The formation of a colorless sediment of silver chloride when silver nitrate solution is added to the studied solution - quality reaction on chloride ion:

AG + CL \u003d AGCL

From sodium chlorides or potassium in the laboratory, you can get chlorine:

2nacl + 3H 2 SO 4 + MnO 2 \u003d 2NAHSO 4 + MNSO 4 + 2H 2 O + CL 2

As an oxidizing agent, not only manganese dioxide, but also Kmno 4, K 2 Cr 2 O 7, KCLO 3 can be used in this method.
Sodium and potassium hypochlorites are part of various household and industrial bleachers. Chlorine lime is also used as a bleach, in addition, it is used as a disinfectant.
Potassium chlorate is used in the production of matches, explosives and pyrotechnic compositions. When heated, it decomposes:
4KCLO 3 \u003d KCL + 3KCLO 4;
2KCLO 3 \u003d 2KCl + O 2 (in the presence of MNO 2).
Potassium perchlorate is also decomposed, but at a higher temperature: KCLO 4 \u003d KCl + 2O 2.

1. Come on the molecular equations of reactions for which ion equations are given in the text of the paragraph.
2. Sust the reaction equations, the data in the text of the paragraph is descriptive.
3. Suggest the equations of reactions characterizing the chemical properties A) chlorine, b) chloride hydrogen (and hydrochloric acid), c) potassium chloride and g) barium chloride.
Chemical properties of chlorine compounds

In different conditions are resistant, various allotropic modifications element sulfur. Under normal conditions simple substance The sulfur is a yellow fragile crystalline substance consisting of eightyatomic molecules:

This is the so-called rhombic sulfur (or -ser) S 8. (The name comes from the crystallographic term characterizing the symmetry of the crystals of this substance). When heated, it melts (113 ° C), turning into a movable yellow liquid consisting of the same molecules. With further heating, the cycles and the formation of very long polymer molecules occurs - the melt darkens and becomes very viscous. This is the so-called -ser n. . Sulfur boils (445 ° C) in the form of dimensional molecules S 2, similar to the structure of oxygen molecules. The structure of these molecules as well as oxygen molecules cannot be described as part of a covalent communication model. In addition, there are other allotropic modifications of sulfur.
In nature, there are deposits of native sulfur, from which it is mined. Most of the produced sulfur is used to produce sulfuric acid. Part of the sulfur use in agriculture to protect plants. Purified sulfur is used in medicine for the treatment of skin diseases.
Of hydrogen compounds Sulfur is the greatest value of hydrogen sulfide (monosulfan) H 2 S. This is a colorless poisonous gas with a smell of rotten eggs. In the water he is a little solvent. Dissolution physician. A slightly degree in an aqueous solution occurs the protolisis of hydrogen sulfide molecules and to an even lesser extent - the hydrosulfide ions generated at the same time (see Appendix 13). Nevertheless, the hydrogen sulfide solution in water is called hydrogen sulfide acid (or hydrogen sulfide water).

In the air, hydrogen sulfide burns:

2H 2 S + 3O 2 \u003d 2H 2 O + SO 2 (with an excess of oxygen).

The high-quality reaction to the presence of hydrogen sulfide in the air is the formation of a black lead sulfide (blackening filter paper, moistened with lead nitrate solution:

H 2 S + PB 2 + 2H 2 O \u003d PBS + 2H 3O

The reaction proceeds in this direction due to the very small solubility of lead sulfide.

In addition to hydrogen sulfide, sulfur forms other sulfans H 2 S n. , for example, Disulfan H 2 S 2, similar to the structure of hydrogen peroxide. It is also very weak acid; Her salt is pyrite Fes 2.

In accordance with the valence capabilities of its sulfur atoms forms two oxide: SO 2 and SO 3. Sulfur dioxide (trivial name - sulfur gas) - colorless gas with a sharp smell causing cough. Sulfur trioxide (the old name is a sulfuric anhydride) is a solid extremely hygroscopic non-elastic substance, when heated turning into molecular. Both acidic oxide. When reaction with water, sulfur and sulfur acid.
In dilute solutions, sulfuric acid - typical severe acid with all the properties characteristic of them.
Clean sulfuric acid, as well as its concentrated solutions - very strong oxidizers, with atoms-oxidizers here are not atoms of hydrogen, but sulfur atoms, moving from the degree of oxidation + Vi into the oxidation degree + iv. As a result, with concentrated sulfuric acid, sulfur dioxide is usually formed with concentrated sulfuric acid.

Cu + 2H 2 SO 4 \u003d Cuso 4 + SO 2 + 2H 2 O;
2kbr + 3H 2 SO 4 \u003d 2KHSO 4 + BR 2 + SO 2 + 2H 2 O.

Thus, with concentrated sulfuric acid, even metals are reacting in a row of voltages to the right of hydrogen (Cu, Ag, Hg). At the same time, some rather active metals (Fe, Cr, Al, etc.) do not react with concentrated sulfuric acid, this is due to the fact that the surface of such metals under the action of sulfuric acid is formed a dense protective film that impedes further oxidation. This phenomenon is called passivation.
Being a two-axis acid, sulfuric acid forms two rows salley: Middle and sour. Acid salts are isolated only for alkaline elements and ammonium, the existence of other acid salts is doubted.
Most of the average sulfates are soluble in water and, since the sulfate ion is practically not an anionic base, are not subjected to hydrolysis on the anion.
Modern industrial production methods for sulfuric acid are based on the production of sulfur dioxide (1st stage), the oxidation of it into the trioxide (2nd stage) and the interaction of sulfur trioxide with water (3rd) stage.

Sulfur dioxide is becoming burning in oxygen sulfur or various sulphides:

S + O 2 \u003d SO 2;
4FES 2 + 11O 2 \u003d 2FE 2 O 3 + 8SO 2.

The process of firing sulfide ores in non-ferrous metallurgy is always accompanied by the formation of sulfur dioxide, which is based on the production of sulfuric acid.
Under normal conditions, sulfur dioxide is impossible to oxidize oxygen. Oxidation is carried out when heated in the presence of a catalyst - vanadium oxide (V) or platinum. Despite the fact that the reaction

2SO 2 + O 2 2SO 3 + Q.

reversible, the exit reaches 99%.
If we pass the resulting gas mixture of sulfur trioxide with air through clean water, most of the sulfur trioxide is not absorbed. To prevent losses, the gas mixture is passed through sulfuric acid or its concentrated solutions. In this case, disinthic acid is formed:

SO 3 + H 2 SO 4 \u003d H 2 S 2 O 7.

The disurban acid solution in sulfur is called oleum and are often represented as a solution of sulfur trioxide in sulfuric acid.
Diluting oleum with water, it is possible to obtain both pure sulfuric acid and its solutions.

1.Conal structural formulas
a) sulfur dioxide, b) sulfur trioxide,
c) sulfuric acid, d) disurban acid.