Skip to content

Name the type of chemical… (Class 10 Science 2024, Q21)

questionbuddy.in/q/cbse-10-science-2024-31-1-1-q21-name-type-chemical-reaction-calcium

ScienceCBSE Class 10 · Board exam 2024, set 31/1/1 · 2 marks · Very short answer

CBSE Class 10 Science 2024: question 21

Set in the CBSE Class 10 board exam of 2024, paper 31/1/1, section B, question 21, for 2 marks. Try it first; the hints and our step-by-step solution are below.

Q21 · 2 marks · Very short answerChemical Reactions and Equations

Name the type of chemical reaction in which calcium oxide reacts with water. Justify your answer by giving balanced chemical equation for the chemical reaction.

Source: official question paper from cbse.gov.in (PDF). See it in the full 2024 board paper, set 31/1/1.

Hints

Open one hint at a time and try again before the next.

Hint 1

Count how many products are formed when quick lime is added to water.

Hint 2

A reaction where two or more substances join to give one product has a special name. What is quick lime turned into?

Step-by-step solution

Each step shows the marks it earns, as an examiner would award them. Checked by an independent re-solve from the question paper.

  1. Type of reaction: Combination reaction (it is also exothermic).

    ½ mark

  2. Justification: two reactants, calcium oxide and water, combine to form a single product, calcium hydroxide.

    ½ mark

  3. Balanced equation: . Here quick lime gives slaked lime.

    1 mark

Answer: Combination reaction: + heat

Where the marks are

  • Names the reaction as a combination reaction (½ mark)
  • Justifies it: a single product is formed from two reactants (½ mark)
  • Writes the balanced equation forming (1 mark)

Revise the chapter

Practise this chapterBoard-style questions from Chemical Reactions and Equations, one at a time, marked against the answer key and marking points.Back to the full paper2024 board paper, set 31/1/1: every question, by section.

The question is transcribed from the official paper; figures are described in words. The solution, hints and chapter tag are ours. Spotted an error? Write tosupport@questionbuddy.in.