Chemistry
Assertion (A): Sulphuric acid acts as an oxidising agent.
Reason (R): Sulphuric acid produces hydrogen on reacting with zinc.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
Answer
Both A and R are true but R is not the correct explanation of A.
Explanation— Sulphuric acid acts as an oxidising agent due to the fact that on thermal decomposition, it yields nascent oxygen [O]. This nascent oxygen oxidises non-metals, metals and inorganic compounds. Hence, the assertion (A) is true.
H2SO4 ⟶ 2H2O + SO2 + [O]
Dilute sulphuric acid reacts with metals like zinc, that is present above hydrogen in the activity series to form metallic sulphate and hydrogen at ordinary temperature. Hence, the reason (R) is true.
Zn + H2SO4 ⟶ ZnSO4 + H2 ↑
But, reason (R) doesn't explain the reason behind oxidising property of sulphuric acid. Hence, reason (R) is not the correct explanation of assertion (A).
Related Questions
Assertion (A): Impurity of arsenic oxide must be removed before passing the mixture of SO2 and air through the catalytic chamber.
Reason (R): Arsenic oxide poisons the catalyst.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
Assertion (A): Concentrated sulphuric acid is kept in air tight bottles.
Reason (R): Air contains impurities, therefore H2SO4 will get spoiled.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
Following are the typical properties of dilute acid. Complete them by inserting suitable words:
(i) Active metal + acid ⟶ …………… + ……………
(ii) Base + Acid ⟶ …………… + ……………
(iii) Carbonate/hydrogen carbonate + Acid ⟶ …………… + ……………
(iv) Sulphite/hydrogen sulphite + Acid ⟶ …………… + ……………
(v) Sulphide + Acid ⟶ …………… + ……………
Name :
(a) The acid formed when sulphur dioxide dissolves in water.
(b) The gas released when sodium carbonate is added to a solution of sulphur dioxide.
(c) Liquid E can be dehydrated to produce ethene.
(d) The gas that can be oxidized to sulphur.
(e) The solution which liberates sulphur dioxide gas from sodium sulphite.
(f) The gas produced on reaction of dilute sulphuric acid with a metallic sulphide.
(g) A dilute mineral acid which forms a white precipitate when treated with barium chloride solution.
(h) The acid which produces sugar charcoal from sugar.
(i) The acid on mixing with lead nitrate solution produces white ppt. which is insoluble even on heating.