State points of difference between homogeneous and heterogeneous mixtures.

Important Questions on Is Matter Around Us Pure?

MEDIUM

9th CBSE

IMPORTANT

Core science chemistry>Chapter 2 - Is Matter Around Us Pure?>EXERCISE 2A>Q 2

Given a solution of substance A, how will you test whether it is saturated or unsaturated with respect to A, at the prevailing temperature? What is observed when a hot saturated solution of a substance is allowed to cool?

EASY

9th CBSE

IMPORTANT

Core science chemistry>Chapter 2 - Is Matter Around Us Pure?>EXERCISE 2A>Q 3

State two characteristics of pure substance.

MEDIUM

9th CBSE

IMPORTANT

Core science chemistry>Chapter 2 - Is Matter Around Us Pure?>EXERCISE 2A>Q 4

Classify the following as homogeneous and heterogeneous mixture:
(a) Soft drink
(b) Wood
(c) Vinegar
(d) Soil
(e) Sugar solution
(f) Filtered tea

HARD

9th CBSE

IMPORTANT

Core science chemistry>Chapter 2 - Is Matter Around Us Pure?>EXERCISE 2A>Q 5

The teacher instructed three students ‘A’, ‘B’ and ‘C’ respectively to prepare a 50% (mass by volume) solution of sodium hydroxide (NaOH). 'A' dissolved 50g of NaOH in 100 mL of water, 'B' dissolved 50g of NaOH in 100 g of water while 'C dissolved 50g of NaOH in water to make 100 mL of solution. Which one of them has made the desired solution and why?

MEDIUM

9th CBSE

IMPORTANT

Core science chemistry>Chapter 2 - Is Matter Around Us Pure?>EXERCISE 2A>Q 6

Arun has prepared 0.01% (by mass) solution of sodium chloride in water. Which of the following correctly represents the composition of the solutions?

HARD

9th CBSE

IMPORTANT

Core science chemistry>Chapter 2 - Is Matter Around Us Pure?>EXERCISE 2A>Q 7

Calculate the mass of sodium sulphate required to prepare its 20% (mass percent) solution in 100 g of water.

MEDIUM

9th CBSE