Science : Ch 01 – Chemical Reactions and Equations

Science : Ch 01 - Chemical Reactions and Equations

This test is designed based on NCERT Syllabus for Class 10 Topics : Chemical Reactions and Equations

Each time random 15 questions will be displaced
So retake the quiz till you have mastered all the questions

1 / 15

Which reaction takes place when layer of silver deposit on copper wire when dipped in silver nitrate solution?

displacement reaction

replacement reaction

oxidation

reduction reaction

2 / 15

Give an example of decomposition reaction taking place in our body.

reproduction

digestion

blood circulation

respiration

3 / 15

Why are anti-oxidants added to fat and oil containing food items?

To prevent oxidation

to increase oxidation

to prevent reduction

all of these

4 / 15

Why are oil and fat containing food items fushed with nitrogen while packing?

to prevent reduction

To prevent rancid

to increase oxidation

none of these

5 / 15

Identify the reducing agent in the following reactions: 2H₂ + O₂ → 2H₂O

O

H2

H2O

H2

6 / 15

When hydrogen sulphide gas is passed through a blue solution of copper sulphate, the colour of the solution fades and a black precipitate is obtained.Name the type of reaction taking place.

double displacement reaction

single displacement reaction

double replacement reaction

all of these

7 / 15

When hydrogen sulphide gas is passed through a blue solution of copper sulphate, the colour of the solution fades and a black precipitate is obtained.Write the chemical name of the black precipitate formed.

hydrogen sulphide

copper sulphide.

hydrogen sulphate

none of these

8 / 15

State the reactions exothermic or endothermic in nature: Dilution of sulphuric acid

endothermic reaction

exothermic reaction

Both 1 & 2

none of these

9 / 15

Sate the reactions exothermic or endothermic in nature: Dissolution of sodium hydroxide in water

endothermic reaction

both 1 & 3

exothermic reaction

all of these

10 / 15

State the reactions are exothermic or endothermic in nature: Dissolution of ammonium chloride in water

exothermic reaction

endothermic reaction

Both 1 & 2

none of these

11 / 15

In the electrolysis of water, name the gases liberated at anode

H2O

Oxygen

Hydrogen

None of these

12 / 15

On heating blue coloured powder of copper (II) nitrate in a boiling tube, copper oxide (black), oxygen gas and a brown gas X is formed. Identify the brown gas X evolved.

X is nitrogen dioxide gas (NO2) that has evolved as brown, choking fumes

X is copper oxide gas that has evolved as brown, choking fumes

X is oxygen gas that has evolved as brown, choking fumes.

none of these

13 / 15

Which of the following gases can be used for the storage of fresh sample of an oil for a long duration?

Carbon dioxide or oxygen

Nitrogen or oxygen

Carbon dioxide or helium

Helium or nitrogen

14 / 15

The following reaction is used for the preparation of oxygen gas in the laboratory: 2KClO₃(s) Heat ⎯ → Catalyst ⎯⎯⎯ 2KCl(s) + 3O₂(g) Which of the following statement(s) is/are correct about the reaction?

It is a decomposition reaction and endothermic in nature

It is a combination reaction

It is a decomposition reaction and accompanied by release of heat

It is a photochemical decomposition reaction and exothermic in nature

15 / 15

One of the following does not happen during a chemical reaction.

Breaking of old chemical bonds and formation of new chemical bonds

Formation of new substances with entirely diferent properties

Atoms of one element change into those of another element to form new products

A rearrangement of atoms takes place to form new products

Your score is

0%

Science : Ch 01 – Chemical Reactions and Equations

Archives

Categories