- Molecular Details: Sulphuric acid has the formula H₂SO₄ and a relative molecular mass of 98.
- Importance: Known as the "King of Chemicals" due to its wide industrial use.
- Historical Name: Previously called oil of vitriol, obtained by heating green vitriol (FeSO₄·7H₂O).
- Natural Occurrence: Found in mineral springs (free state) and in minerals like barytes (BaSO₄), gypsum (CaSO₄·2H₂O), and kieserite (MgSO₄·H₂O).
- Laboratory Preparation: Prepared by oxidising SO₂ with O₂, Cl₂, or Br₂ in water, or by reacting sulphur with concentrated nitric acid.
Definitions [4]
Define the following term:
Constant boiling mixture
Constant boiling mixture : Mixture which boils without any change in composition is known as constant boiling mixture.
Define the following term : Oleum
Oleum : Oleum is called pyrosulphuric acid or orthosulphuric acid. Formula is H2S2O7.
Define the following term : Hygroscopic substance
Hygroscopic substance : The compound which absorbs water vapour from the atmosphere.
Define the following term : Dehydrating agent
Dehydrating agent : The compound which has more affinity for water. It removes atoms of hydrogen and oxygen in the form of waterfrom the composition of a substance.
Key Points
Key Points: Sulphuric Acid
Key Points: Manufacture of Sulphuric Acid
- SO₂ Production: Made by burning sulphur or roasting iron pyrites (FeS₂).
- Gas Purification: Dust, moisture, and arsenic are removed to protect the catalyst.
- Catalytic Oxidation: SO₂ + O₂ → SO₃ using V₂O₅ at 450°C in the contact tower.
- SO₃ Absorption: SO₃ is absorbed in H₂SO₄ to form oleum (not directly in water).
- Final Step: Oleum is diluted with water to make concentrated sulphuric acid.
Key Points: Physical Properties of Sulphuric Acid
| Property | Description |
|---|---|
| Colour | Colourless |
| Odour | Odourless |
| Taste | Slightly sour |
| Nature | Dense, oily, and hygroscopic liquid |
| Density | 1.85 g/cm³ (pure) |
| Boiling Point | 338°C |
| Melting Point | Freezes at 10.4°C |
| Solubility | Fully soluble in water |
| Conductivity | Pure acid is a poor conductor; dilute acid conducts well |
| Boiling Mixture | Forms a constant boiling mixture at 338°C (98.5% acid) |
| Effect on Skin | Corrosive; chars skin black |
Key Points: Chemical Properties of Sulphuric Acid
- Acidic Nature: H₂SO₄ is a strong dibasic acid—forms acid and normal salts.
- Dilute Acid: Reacts with metals, bases, carbonates, sulphides, and sulphites to release gases like H₂, CO₂, H₂S, and SO₂.
- Concentrated Acid: Acts as a strong oxidiser—gives off nascent oxygen.
- Dehydrating Agent: Removes water from salts and organics (e.g., sugar gets charred).
- Non-Volatile: Used to make volatile acids and insoluble sulphates (e.g., PbSO₄, BaSO₄).
Important Questions [44]
- Write a Balanced Chemical Equation for Each of the Following Reactions : Action of Dilute Sulphuric Acid on Sodium Hydroxide.
- Write a Balanced Chemical Equation for Each of the Following Reactions : Action of Dilute Sulphuric Acid on Zinc Sulphide.
- Ferrous Sulphate Solution and Ferric Sulphate Solution. (Using Sodium Hydroxide Solution)
- Identify the following: The element having electronic configuration 2, 8, 6.
- Arrange the following as per the instruction given in the bracket: Sulphuric acid, Phosphoric acid, Acetic acid (increasing order of number of replaceable H atoms per molecule).
- Complete the Following Equations : S + Conc.Hno3 →
- Complete the Following Equations : C + Cons. H2so4
- Write balanced chemical equations for the action of dilute sulphuric acid on sodium sulphite.
- State Your Observations When Concentrated Sulphuric Acid is Added to Sugar Crystals
- A, B, C, and D Summarize the Properties of Sulphuric Acid Depending on Whether It is Dilute Or Concentrated Preparation of Hydrogen Chloride Gas and Preparation of Copper Sulphate from Copper Oxide and and an Action of Conc. Sulphuric Acid on Sulphur.
- The Acid Which is Used in the Preparation of a Volatile Acid
- Identify the acid in the following case: The acid which produces sugar charcoal from sugar.
- Identify the acid in the following case: The acid on mixing with lead nitrate solution produces a white precipitate, which is insoluble even on heating.
- Give Appropriate Scientific Reasons For The Electrical Conductivity of Acetic Acid is Less in Comparison to the Electrical Conductivity of Dilute Sulphuric Acid at a Given Concentration.
- Give Balanced Chemical Equations for the Action of Sulphuric Acid on the Following: Potassium Hydrogen Carbonate.
- Give Balanced Chemical Equations for the Action of Sulphuric Acid on the Following: Sulphur
- In the Contact Process for the Manufacture of Sulphuric Acid Give the Equations for the Conversion of Sulphur Trioxide to Sulphuric Acid.
- Quicklime is not used to dry HCl gas because _____.
- Distinguish between the given pair of compounds using the test given within brackets: Sodium nitrate and sodium sulphite (using dilute sulphuric acid).
- Distinguish Between the Given Pairs of Compounds Using the Test Given Within Brackets: Dilute Sulphuric Acid and Dilute Hydrochloric Acid (Using Barium Chloride Solution)
- State the Conditions Required for the Given Reaction to Take Place: Any Two Conditions for the Conversion of Sulphur Dioxide to Sulphur Trioxide
- State the Inference Drawn from the Following Observations: Salt S is Prepared by Reacting Dilute Sulphuric Acid with Copper Oxide. Identify S.
- Give One Equation to Show the Following Properties of Sulphuric Acid: Dehydrating Property
- Give One Equation to Show the Following Properties of Sulphuric Acid: Acidic Nature
- Give One Equation to Show the Following Properties of Sulphuric Acid: as a Non-volatile Acid
- Which Property of Sulphuric Acid is Shown by the Reaction of the Concentrated Sulphuric Acid with Ethanol?
- Which property of sulphuric acid is shown by the reaction of the concentrated sulphuric acid with carbon?
- The salt is formed when concentrated sulphuric acid reacts with KNO3 above 200°C.
- The property exhibited by concentrated sulphuric acid when it is used to prepare hydrogen chloride gas from potassium chloride is ______.
- Convert the following reaction into a balanced chemical equation: Sodium hydroxide to sodium sulphate using sulphuric acid.
- Differentiate between the following pair based on the criteria given in the bracket: Cane sugar and hydrated copper sulphate [using concentrated H2SO4]
- Rewrite the following statement by adding the correct word, as shown in the example: Example: Given Statement: Ammonia changes moist red litmus to blue. Sulphuric acid acts as a dehydrating agent.
- Hydrogen chloride gas is prepared in the laboratory by the action of concentrated sulphuric acid on sodium chloride. What is the property of sulphuric acid that makes it a suitable reagent?
- State One Relevant Observation for Given Reactions: Addition of Ethyl Alcohol to Acetic Acid in the Presence of Concentrated Sulphuric Acid
- State One Relevant Observation for Given Reactions: Action of Concentrated Sulphuric Acid on Hydrated Copper Sulfate
- How Will You Distinguish Between Dilute Hydrochloric Acid and Dilute Sulphuric Acid Using Lead Nitrate Solution?
- Write Balanced Chemical Equations to Show The Oxidizing Action of Conc. Sulphuric Acid on Carbon
- Write Balanced Chemical Equations to Show The Dehydrating Property of Conc. Sulphuric Acid with Sugar.
- Write Balanced Chemical Equations to Show How So3 is Converted to Sulphuric Acid in the Contact Process.
- Hydrogen chloride gas is prepared in the laboratory by the action of concentrated sulphuric acid on sodium chloride. State the method of collection of the gas formed above.
- Write a Balanced Chemical Equation for the Following: Action of Concentrated Sulphuric Acid on Sulphur.
- Hydrogen chloride gas is prepared in the laboratory by the action of concentrated sulphuric acid on sodium chloride. Give a balanced chemical equation for the above reaction.
- The solution of this compound produces dirty green precipitate with NaOH.
- The compound that will produce sulphur dioxide gas when reacted with dilute HCl.
