EASY
9th CBSE
IMPORTANT
Earn 100

State two characteristics of pure substance.

Important Questions on Is Matter Around Us Pure?

MEDIUM
9th CBSE
IMPORTANT

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

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
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
Calculate the mass of sodium sulphate required to prepare its 20% (mass percent) solution in 100 g of water.
MEDIUM
9th CBSE
IMPORTANT

What is a true solution? State three characteristics of a true solution.

MEDIUM
9th CBSE
IMPORTANT
Give three differences between a colloidal solution and a suspension.
MEDIUM
9th CBSE
IMPORTANT
What are colloidal solutions? How do they differ from true solutions?
HARD
9th CBSE
IMPORTANT
During an experiment, the students were asked to prepare a 10% (Mass/Mass) solution of sugar in water. Ramesh dissolved 10 g of sugar in 100 g of water while Sarika prepared it by dissolving 10 g of sugar in water to make 100 g of the solution.
(a) Are the two solutions of the same concentration.
(b) Compare the mass % of the two solutions.