How is sulphuric acid manufactured by contact process. Write the action of Conc. H2SO4 on [6+4] i) Glucose…

Question

How is sulphuric acid manufactured by contact process. Write the action of Conc. H2SO4 on [6+4] i) Glucose ii) Phosphorous iii) Copper Give an important use of Conc. H2SO4 .

Padhai · Accepted Answer

Manufacture of Sulphuric Acid by the Contact Process Sulphuric acid ( H2SO4 ) is one of the most important industrial chemicals and is manufactured on a large scale by the contact process . This process involves the following key steps: 1. Production of Sulphur Dioxide ( SO2 ) Sulphur or sulphide ores (e.g., pyrite, FeS2 ) are burned in excess air to produce sulphur dioxide. S + O2 SO2 (Exothermic reaction) Sulphur is melted and sprayed into a furnace where it burns in air to form SO2 . Impurities like arsenic and dust are removed by passing the gas through dust chambers and electrostatic precipitators . 2. Oxidation of SO2 to SO3 (Contact Process) The SO2 gas is mixed with more air and passed over a vanadium(V) oxide ( V2O5 ) catalyst at 450°C and 1–2 atm pressure . 2 SO2 + O2 [ V2O5]450°C 2 SO3 The reaction is exothermic , so a moderate temperature (450°C) is maintained to maximize yield (Le Chatelier’s principle). The catalyst ( V2O5 ) is used to speed up the reaction without being consumed. 3. Conversion of SO3 to Oleum ( H2S2O7 ) SO3 is highly reactive and is dissolved in 98% concentrated sulphuric acid to form oleum (pyrosulphuric acid) : SO3 + H2SO4 H2S2O7 Oleum is stored and transported because SO3 cannot be dissolved directly in water (it forms a mist of H2SO4 droplets, which is difficult to handle). 4. Dilution of Oleum to Produce Concentrated H2SO4 Oleum is diluted with water to produce 98% concentrated sulphuric acid : H2S2O7 + H2O 2H2SO4 The reaction is highly exothermic, so water is added slowly to oleum to prevent splattering. Purification and Packaging The final product is purified by distillation to remove impurities. Concentrated H2SO4 (98%) is stored in lead lined iron tanks to prevent corrosion. Action of Concentrated H2SO4 (i) Action on Glucose ( C6H12O6 ) Concentrated H2SO4 acts as a dehydrating agent and removes water molecules from glucose, leading to carbonization (blackening) . C6H12O6 [conc.\ H2SO4] 6C + 6H2O The glucose is first dehydrated to form charcoal (C) and water. The reaction is highly exothermic and results in the formation of a black residue. (ii) Action on Phosphorus ( P4 ) Concentrated H2SO4 oxidizes phosphorus to form phosphorus pentoxide ( P4O10 ) and sulphur dioxide ( SO2 ): P4 + 10H2SO4 4H3PO4 + 10SO2 + 4H2O The reaction produces white fumes of P4O10 (which reacts with moisture to form phosphoric acid, H3PO4 ). SO2 gas is also evolved, which has a choking smell. (iii) Action on Copper ( Cu ) Concentrated H2SO4 acts as an oxidizing agent and oxidizes copper to form copper(II) sulphate ( CuSO4 ) and sulphur dioxide ( SO2 ): Cu + 2H2SO4 CuSO4 + SO2 + 2H2O The reaction is slow at room temperature but speeds up upon heating. A blue solution of CuSO4 is formed, and SO2 gas (with a pungent smell) is evolved. Important Use of Concentrated H2SO4 One of the most important uses of concentrated H2SO4 is in the manufacture of fertilizers , particularly: Ammonium sulphate ( (NH4)2SO4 ) – Used as a nitrogenous…

How is sulphuric acid manufactured by contact process. Write the action of Conc. H2SO4 on [6+4] i) Glucose ii) Phosphorous iii) Copper Give an important use of Conc. H2SO4 .

Manufacture of Sulphuric Acid by the Contact Process

1. Production of Sulphur Dioxide ( $SO X_{2}$ )

2. Oxidation of $SO X_{2}$ to $SO X_{3}$ (Contact Process)

3. Conversion of $SO X_{3}$ to Oleum ( $H X_{2} S X_{2} O X_{7}$ )

4. Dilution of Oleum to Produce Concentrated $H X_{2} SO X_{4}$

Purification and Packaging

Action of Concentrated $H X_{2} SO X_{4}$

(i) Action on Glucose ( $C X_{6} H X_{12} O X_{6}$ )

(ii) Action on Phosphorus ( $P X_{4}$ )

(iii) Action on Copper ( $Cu$ )

Important Use of Concentrated $H X_{2} SO X_{4}$

Discussion

More Chemistry questions

How is sulphuric acid manufactured by contact process. Write the action of Conc. H2SO4 on [6+4] i) Glucose ii) Phosphorous iii) Copper Give an important use of Conc. H2SO4 .

Manufacture of Sulphuric Acid by the Contact Process

1. Production of Sulphur Dioxide (SOX2​)

2. Oxidation of SOX2​ to SOX3​ (Contact Process)

3. Conversion of SOX3​ to Oleum (HX2​SX2​OX7​)

4. Dilution of Oleum to Produce Concentrated HX2​SOX4​

Purification and Packaging

Action of Concentrated HX2​SOX4​

(i) Action on Glucose (CX6​HX12​OX6​)

(ii) Action on Phosphorus (PX4​)

(iii) Action on Copper (Cu)

Important Use of Concentrated HX2​SOX4​

Discussion

More Chemistry questions

1. Production of Sulphur Dioxide ( $SO X_{2}$ )

2. Oxidation of $SO X_{2}$ to $SO X_{3}$ (Contact Process)

3. Conversion of $SO X_{3}$ to Oleum ( $H X_{2} S X_{2} O X_{7}$ )

4. Dilution of Oleum to Produce Concentrated $H X_{2} SO X_{4}$

Action of Concentrated $H X_{2} SO X_{4}$

(i) Action on Glucose ( $C X_{6} H X_{12} O X_{6}$ )

(ii) Action on Phosphorus ( $P X_{4}$ )

(iii) Action on Copper ( $Cu$ )

Important Use of Concentrated $H X_{2} SO X_{4}$