Class 9 Science - Chapter Is Matter Around Us Pure NCERT Solutions | How will you separate a mixture containi

How are sol, solution and suspension different from each other?

Name the technique to separate

(i) butter from curd,
(ii) salt from sea-water,
(iii) camphor from salt.

Differentiate between homogeneous and heterogeneous mixtures with examples.

Identify the solutions among the following mixtures.

(a) Soil
(b) Sea water
(c) Air
(d) Coal
(e) Soda water.

List the points of differences between homogeneous and heterogeneous mixtures.

Explain the following giving examples.

(a) saturated solution
(b) pure substance
(c) colloid
(d) suspension

Write the steps you would use for making tea. Use the words solution, solvent, solute, dissolve, soluble, insoluble, filtrate and residue.

Classify the following into elements, compounds and mixtures.

(a) Sodium
(b) Soil
(c) Sugar solution
(d) Silver
(e) Calcium carbonate
(f) Tin
(g) Silicon
(h) Coal
(i) Air
(j) Soap
(k) Methane
(l) Carbon dioxide
(m) Blood

Which of the following will show “Tyndall effect”?

(a) Salt solution
(b) Milk
(c) Copper sulphate solution
(d) Starch solution.

Which separation techniques will you apply for the separation of the following?

(a) Sodium chloride from its solution in water.
(b) Ammonium chloride from a mixture containing sodium chloride and ammonium chloride.
(c) Small pieces of metal in the engine oil of a car.
(d) Different pigments from an extract of flower petals.
(e) Butter from curd.
(f) Oil from water.
(g) Tea leaves from tea.
(h) Iron pins from sand.
(i) Wheat grains from husk.
(j) Fine mud particles suspended in water.

Which of the following has more inertia: (a) a rubber ball and a stone of the same size? (b) a bicycle and a train? (c) a five-rupees coin and a one-rupee coin?

State the universal law of gravitation.

Which of the following are matter?

Chair, air, love, smell, hate, almonds, thought, cold, cold-drink, smell of perfume.

A force of 7 N acts on an object. The displacement is, say 8 m, in the direction of the force (Fig. 11.3). Let us take it that the force acts on the object through the displacement. What is the work done in this case?

How does the sound produced by a vibrating object in a medium reach your ear?

In a reaction, 5.3 g of sodium carbonate reacted with 6 g of ethanoic acid. The products were 2.2 g of carbon dioxide, 0.9 g water and 8.2 g of sodium observations are in agreement with the law of conservation of mass.

sodium carbonate + ethanoic acid → sodium ethanoate + carbon dioxide + water

What are canal rays?

State any two conditions essential for good health.

How is our atmosphere different from the atmospheres on Venus and Mars?

Who discovered cells, and how?

Gravitational force on the surface of the moon is only 1/6 as strong as gravitational force on the earth. What is the weight in newtons of a 10 kg object on the moon and on the earth?

If number of electrons in an atom is 8 and number of protons is also 8, then (i) what is the atomic number of the atom? and (ii) what is the charge on the atom?

An object experiences a net zero external unbalanced force. Is it possible for the object to be travelling with a non-zero velocity? If yes, state the conditions that must be placed on the magnitude and direction of the velocity. If no, provide a reason.

The potential energy of a freely falling object decreases progressively. Does this violate the law of conservation of energy? Why?

Why do organisms need water?

Differentiate between parenchyma, collenchyma and sclerenchyma on the basis of their cell wall.

How are pteridophytes different from the phanerogams?

Under which of the following conditions is a person most likely to fall sick?
(a) when she is recovering from malaria.
(b) when she has recovered from malaria and is taking care of someone suffering from chicken-pox.
(c) when she is on a four-day fast after recovering from malaria and is taking care of someone suffering from chicken-pox. Why?

An object of mass 40 kg is raised to a height of 5 m above the ground. What is its potential energy? If the object is allowed to fall, find its kinetic energy when it is half-way down.

Name the following.

(a) Tissue that forms the inner lining of our mouth.
(b) Tissue that connects muscle to bone in humans.
(c) Tissue that transports food in plants.
(d) Tissue that stores fat in our body.
(e) Connective tissue with a fluid matrix.
(f) Tissue present in the brain.