CBSE Class 10 Board Examination Practice Quiz

Question 1

Which of the following observations most clearly indicates that a chemical reaction has taken place when zinc granules are added to dilute hydrochloric acid?

Accepted Answer

The zinc granules become smaller and bubbles of a gas are produced

Question 2

What is the balanced equation for the reaction between magnesium and oxygen?

Accepted Answer

2Mg + O2 → 2MgO

Question 3

In the reaction MnO2 + 4HCl → MnCl2 + 2H2O + Cl2, which substance is oxidised?

Accepted Answer

HCl

Question 4

When lead nitrate solution is mixed with potassium iodide solution, a yellow precipitate is formed. Which equation correctly represents this reaction?

Accepted Answer

Pb(NO3)2 + 2KI → PbI2 + 2KNO3

Question 5

Which statement correctly explains why respiration is considered an exothermic reaction?

Accepted Answer

Glucose breaks down and releases energy along with carbon dioxide and water

CBSE Class 10 Board Examination

Practice Quizzes

Chemical Reactions and Equations Fundamentals — Free CBSE Class 10 Board Examination Quiz