AP EAMCET202125 Aug 2021Morning ShiftChemistryp Block Elements (Group 15, 16, 17 & 18)Actual
Which of the following pairs of reactions give H ₂ gas as a product upon hydrolysis?
Options
- A(i) Ba H ₂ O Products (ii) BaO ₂ H ₂ O Products
- B(i) Ca H ₂ O Products (ii) CaH ₂ H ₂ O Products
- C(i) K H ₂ O Products (ii) K ₂ O H ₂ O Products
- D(i) Na H ₂ O Products (ii) Na ₂ O ₂ H ₂ O Products
Correct answer
B. (i) Ca H ₂ O Products (ii) CaH ₂ H ₂ O Products
Step-by-step solution
When calcium metal is dropped in water, it begins to bubble vigorously and react with the water, producing hydrogen gas and a cloudy white precipitate of calcium hydroxide. Calcium metal Ca +2 H ₂ O Calcium hydroxide Ca ( OH )₂ + Hydrogen gas H ₂ The reaction of CaH ₂ with water can be represented by Calcium hydride CaH ₂ +2 H ₂ O Calcium hydroxide Ca ( OH )₂ + Hydrogen gas 2 H ₂ The two hydrolysis products, H ₂ and Ca ( OH )₂ can be readily separated from the dried solvent.