HARD
9th CBSE
IMPORTANT
Earn 100

A student tested the solubility of different substances in water at different temperatures and collected the data as given below.

Substance dissolved

Temperature in K

283           293         313           333             353

Solubility
1. Potassium nitrate 21 32 62 106 167
2. Sodium chloride 36 36 36 37 37
3. Potassium chloride 35 35 40 46 54
4. Ammonium chloride 24 37 41 55 66

The solubility values in the table are given as grams of substance dissolved in 100 grams of water to form a saturated solution. Now answer the following question: 

What mass of potassium nitrate would be needed to produce its saturated solution in 50 grams of water at 313 K?

Important Questions on Is Matter Around Us Pure? (Elements, Compounds and Mixtures)

HARD
9th CBSE
IMPORTANT
Secondary Chemistry>Chapter 2 - Is Matter Around Us Pure? (Elements, Compounds and Mixtures)>Questions as per the Guidelines of CBSE>Q 1

A student tested the solubility of different substances in water at different temperatures and collected the data as given below.

Substance dissolved

Temperature in K

283           293         313           333             353

Solubility
1. Potassium nitrate 21 32 62 106 167
2. Sodium chloride 36 36 36 37 37
3. Potassium chloride 35 35 40 46 54
4. Ammonium chloride 24 37 41 55 66

The solubility values in the table are given as grams of substance dissolved in 100 grams of water to form a saturated solution. Now answer the following question:

The student prepares a saturated solution of potassium chloride in water at 353 K and leaves the solution to cool at room temperature. What would be observed as the solution cools? Explain.

MEDIUM
9th CBSE
IMPORTANT
Secondary Chemistry>Chapter 2 - Is Matter Around Us Pure? (Elements, Compounds and Mixtures)>Questions as per the Guidelines of CBSE>Q 1

A student tested the solubility of different substances in water at different temperatures and collected the data as given below.

Substance dissolved

Temperature in K

283           293         313           333             353

Solubility
1. Potassium nitrate 21 32 62 106 167
2. Sodium chloride 36 36 36 37 37
3. Potassium chloride 35 35 40 46 54
4. Ammonium chloride 24 37 41 55 66

The solubility values in the table are given as grams of substance dissolved in 100 grams of water to form a saturated solution. Now answer the following question:

 Find the solubility of each salt at 293 K. Which salt has the highest solubility at this temperature?

MEDIUM
9th CBSE
IMPORTANT
Secondary Chemistry>Chapter 2 - Is Matter Around Us Pure? (Elements, Compounds and Mixtures)>Questions as per the Guidelines of CBSE>Q 1

A student tested the solubility of different substances in water at different temperatures and collected the data as given below.

Substance dissolved

             Temperature in K

283           293         313           333             353

                  Solubility
1. Potassium nitrate 21 32 62 106 167
2. Sodium chloride 36 36 36 37 37
3. Potassium chloride 35 35 40 46 54
4. Ammonium chloride 24 37 41 55 66

The solubility values in the table are given as grams of substance dissolved in 100 grams of water to form a saturated solution. Now answer the following question:

What is the effect of change of temperature on the solubility of a salt?

HARD
9th CBSE
IMPORTANT
Secondary Chemistry>Chapter 2 - Is Matter Around Us Pure? (Elements, Compounds and Mixtures)>Questions as per the Guidelines of CBSE>Q 2
Describe the steps to separate each component from a mixture containing iron filings, sulphur, sodium chloride and sand.
HARD
9th CBSE
IMPORTANT
Secondary Chemistry>Chapter 2 - Is Matter Around Us Pure? (Elements, Compounds and Mixtures)>Questions as per the Guidelines of CBSE>Q 3
Define a colloid and write its other names. Give an example of each one of:
(a) sol 
(b) emulsion 
(c) gel 
(d) aerosol
 
HARD
9th CBSE
IMPORTANT
Secondary Chemistry>Chapter 2 - Is Matter Around Us Pure? (Elements, Compounds and Mixtures)>Questions on Higher Order Thinking Skills (HOTS)>Q 1
The boiling points of argon, nitrogen and oxygen are -1800C, -1960C and -1830C respectively. Which of these gases will distill first from their mixture in the air? Justify your answer. 
 
HARD
9th CBSE
IMPORTANT
Secondary Chemistry>Chapter 2 - Is Matter Around Us Pure? (Elements, Compounds and Mixtures)>Questions on Higher Order Thinking Skills (HOTS)>Q 2
On adding dil. HCl to a mixture of iron filings and sulphur an odorless gas is produced, but a gas with rotten eggs is produced when the same acid is added to iron sulphide. Explain this difference by chemical equations. 
EASY
9th CBSE
IMPORTANT
Secondary Chemistry>Chapter 2 - Is Matter Around Us Pure? (Elements, Compounds and Mixtures)>Questions on Higher Order Thinking Skills (HOTS)>Q 3
Oxygen is an element with non-metallic nature. What is its molecular formula?