Students rely on Kerala Syllabus 9th Standard Chemistry Notes Pdf Download Chapter 6 Solutions Extra Questions and Answers to help self-study at home.
Kerala Syllabus Std 9 Chemistry Chapter 6 Solutions Extra Questions and Answers
Question 1.
Some solutions are given below.
Brass, Sugar solution, Mixture of alcohol and water, Soda water
a. Which among these has solid solute and solid solvent?
b. Which are the solute and solvent in the mixture of alcohol and water?
c. Which among these has gaseous solute?
Answer:
a. Brass
b. Solute: Alcohol
Solvent: Water
c. Soda water
Question 2.
The constituents of Brass are Zinc and ………………….
Answer:
Copper
Question 3.
a. Which is the solute present in dilute hydrochloric acid?
b. What is meant by the concentration of a solution?
Answer:
a. Hydrochloric acid
b. The amount of solute dissolved in a fixed amount of solvent is called the concentration of the solution.
Question 4.
What do you mean by crystallisation?
Answer:
The process by which crystals of the solute are formed when a supersaturated solution is cooled slowly is called crystallisation.
Question 5.
A solution is formed when a solute dissolves in a solvent.
a. What is meant by the concentration of a solution?
b. By which name the solution containing a very small amount of solute is known?
c. What is a saturated solution?
Answer:
a. The amount of solute dissolved in a fixed amount of solvent is called the concentration of solution.
b. Dilute solution
c. A solution obtained by dissolving a maximum amount of solute at a given temperature is known as a saturated solution.
Question 6.
a. What is the difference between a saturated solution and a supersaturated solution?
b. Write two factors that influence the solubility.
Answer:
a. A solution obtained by dissolving a maximum amount of solute at a given temperature is known as a saturated solution.
A solution that contains more amount of solute than what is required to saturate it at high temperature is known as a supersaturated solution.
b. Nature of solute and the temperature.
Question 7.
Analyse the table and answer the questions given below
| Mixture A | Mixture B | Mixture C |
| • Particles cannot be separated by filtration • On passing an intense beam of light, its path is visible. |
• Particles can be separated by filtration | • Particles cannot be separated by filtration • On passing an intense beam of light, its path is not visible. |
a. Which one of the given mixtures represents a true solution?
b. In which mixture particles settle down when kept undisturbed for some time?
c. To which of these mixtures does milk belong?
Answer:
a. Mixture C (True solution)
b. Mixture B (Suspension)
c. Mixture A (Colloid)
Question 8.
Find the relation and fill up suitably.
Milk : Colloid
Muddy water : ……………………
Answer:
Suspension
Question 9.
Haven’t you noticed the caption “Shake well before use” in certain medicine bottles? Which class does the substance in them belong to?
(Solution, Colloid, Suspension)
Answer:
Suspension
Question 10.
Classify the following substances into True solution, Colloid and Suspension.
Muddy water, Fog, Milk, Sugar solution, Copper sulphate solution, mixture of chalk powder and water
Answer:
| True Solution | Colloid | Suspension |
| Sugar solution Copper sulphate solution |
Milk Fog |
Muddy water Mixture of chalk powder and water |
Question 11.
Identify the true solution.
(Muddy water, Milk, Saltwater, Rice water)
Answer:
Saltwater
Question 12.
Classify the following mixtures into homogeneous and heterogeneous.
Sugar solution, Salt and sand, Air, Muddy water
Answer:
| Homogeneous mixtures | Heterogeneous mixtures |
| Sugar solution Air |
Salt and sand Muddy water |
Question 13.
Some statements are given below. Pick out the statements suitable for true solutions.
i. If an intense beam of light is passed, the path of the light becomes visible.
ii. Components cannot be separated by filtration using a filter paper.
iii. The substance settles down on standing for some time.
iv. If an intense beam of light is passed, the path of the light does not become visible.
Answer:
ii. Components cannot be separated by filtration using a filter paper.
iv. If an intense beam of light is passed, the path of the light does not become visible.
Question 14.
The components of a mixture of chalk powder and water can be separated using filter paper.
a) To which type does this mixture belong?
(True solution, Colloid, Suspension)
b) Write any two other characteristics of mixture belonging to this type.
Answer:
a) Suspension
b) When kept undisturbed, particles settle down.
Particles can be separated by filtration.
Question 15.
What are the use of stabilisers in artificial soft drinks?
Answer:
Stabilisers are added to retain the mixture for a long time without settling.
Question 16.
Identify the relation and fill up the blank.
Tartrazine: Yellow colour
__________ : Red colour
Answer:
Erythrosine
Question 17.
Give examples of stabilisers used in soft drinks.
Answer:
Brominated vegetable oil, sucrose acetate isobutyrate, glyceryl ester of rosin, etc.
Question 18.
Substances added to present the settling of particles in soft drinks are called __________.
(colloids, stabilisers, suspensions)
Answer:
Stabilisers
Question 19.
What is the impact of the chemicals in soft drinks on our bodies?
Answer:
Increases acidity in the stomach that leads to ulcers and cancer, Chemicals like Ajinomoto affect our nervous system, Cause indigestion, and cause addiction (tendency to use again and again).’
Question 20.
For what purposes chemicals are used in soft drinks.
Answer:
To prevent the setting of components, to add colour, to add flavour and to add sour taste*.
Question 21.
Name the chemical substance added to artificial drinks to obtain a sour taste.
(Tartrazine, Phosphoric acid, Allyl hexanoate)
Answer:
Phosphoric acid