Assignment Questions for Class 9th
Q. 1: Why does ice float on water? As the temperature decreases, the thing becomes solid with more density,
then why ice is lighter than water?
Q. 2: We say that a Sponge is a Solid. But how can it be compressible?
Q. 3: How Does the Expansion of solids help to auto off in iron box?
Q. 4: Ghee freezed at room temperature, whereas mustard oil didn't? Which of these has a higher melting
point and lower intermolecular space?
Q. 5: What is the state of matter of matter of fire? Solid, Liquid, or gas explain.
Q. 6: Camphor disappears without leaving any residue. Explain?
Q. 7: Why do we feel cool when we touch a piece of ice?
Q.8: Convert the following:a) 573K
b) 36 deg C
c) 373 deg C
Q. 9: Both the process of evaporation and boiling involves the change of state from liquid to gas but
still they are different from each other. Justify.
Q. 10: Why is Kelvin considered as the best scale for measuring the temperature?
Q. 11: How can you show that evaporation causes cooling?
Q. 12: What is the significance of boiling point & melting point of a substance?
Q. 13: When we put CuSO4 in water, after sometime we find the soln. turns blue. Why? Also, on heating
it, what change will occur?
Q. 14: How can you justify that table is a solid?
Q.15: Arrange the following in decreasing order of force of attraction: Water, Salt, Oxygen
Q.16: State characteristics of matter demonstrated by:
a) diffusion
b) Brownian motion.
Q.17: When an incense stick (agarbatti) is lighted in one corner of a room, its fragrance spreads in
the whole room quickly.
Q. 18: The boiling point of alcohol isn 78 deg C. What is this temperature on Kelvin scale?
Q. 19: The Kelvin scale temperature is 0 K. What is the corresponding Celsius scale temperature?
Q. 20: What is Latent Heat of Fusion?
Q. 21: Define latent heat of Vaporization?
Q. 22: why or how does non-volatile impurity forms strong bond with water.
Q. 23: How does the boiling point of a liquid varies with pressure
Q. 24: When we compress two ice cubes some ice in between the ice cubes melts. Why or How does this
happen?
Q. 25: How does the presence of non volatile impurity increases boiling point of pure water?
Q. 26: How are particles of matter affected with increase or reducing pressure on the matter at a given
temperature?
Q. 28: Which of the following will show “Tyndall effect”?
(a) salt solution (b) milk (c) copper sulphate solution (d) starch solution.
Q.29: 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
Q.30: In the formation of sodium chloride from its constituent elements, do the properties of its elements
change. Explain.
Q. 31: If evaporation causes cooling effect then why is it like that when we heat water evaporation occurs
but no cooling effect is there?
Q. 32: 1)Why surgeons often spray ether on skin before performing minor surgery 2)why do we se water
droplets on the outer surface of a glass tumbler containing ice cold water 3) why do we sprinkle water on the
roof or on the open ground ? 4)why are we able to sip hot tea faster from a saucer rather than a cup? 5) why
does our palm feel cold when we put some perfume on it?
Q. 33: In the chapter level test, it was asked at what temperature does evaporation occur. The correct answer
was at all temperatures. I couldn't understand why because at all temperature means that it can even go to -1
degree celsius. Then why is the answer at all temperatures.
Q. 34: At what temperature does evaporation occur?
A. At all temperatures
B. At a very low temperature
C. At a very high temperature
D. None of the above statements is true
Which one is correct and why explain.
Q. 35: what is the difference between evaporation and condensation?
i know what is evaporation and i also know what condensation is but i want to ask that what is the difference
between them?
Q. 36: If we leave water at 0'C, then it freezes and vice-verse. Is that true? If it is, then in what state does
water exist at 0'C?
Q. 37: Fusion is a process where ice (solid)converts into water(liquid).Melting is also a process where the
solid converts into liquid then what is the difference between fusion and melting?
Q. 38: Why do pipes burst in winters?
Q. 39: Why is tv solid at room temperature?
Q. 40: Why are Steam Burns more severe than Burns of Boiling Water ?
Q. 41: Will the rate of diffusion increase with the temperature in liquid state?
Q. 42: Rate of diffusion is directly proportional to the temperature of the substance. is this applicable to all
states of matter. How and why?
Q. 43: Rate of diffusion is inversely proportional to the density of liquid then what about other states of
matter?
Q. 44: Will there be a change in the rate of motion of particles when there is a change in the state of matter?
Q. 45: Camphor disappears without leaving any residue. Explain?
Q. 46: How can you justify that table is a solid?
Q. 47: State characteristics of matter demonstrated by :
a) diffusion
b) Brownian motion
Q. 49: When an incense stick (agarbatti) is lighted in one corner of a room, its fragrance spreads in the
whole room quickly. Which characteristic of the particles of matter is illustrated by this observation?
Q. 50: The boiling point of alcohol is 78 deg C. What is this temperature on Kelvin scale?
Q. 51: The Kelvin scale temperature is 0 K. What is the corresponding Celsius scale temperature?
Q. 52: What is distillation?
Q. 53: How is blood a heterogeneous substance?
Q. 54: Calculate the mass of sodium sulphate required to prepare its 20% (mass percent) solution in 100g of
water?
Q. 55: Rajeev has prepared 0.01% (by mass) solution of sodium chloride in water, calculate the composition
of solution. How do you do it?
Q. 56: How to separate components from mixture containing sulphur, charcoal, potassium nitrate?
Q. 57: Acetone evaporates in normal room temp. Why do we have to heat it to its boiling point?
Q. 58: Action of heat on blue vitriol is a physical as well as chemical change. Justify.
Q. 59: How would you separate a mixture of NH4Cl and I2?
Q. 60: How can you prove that air is a mixture?
Q. 61: Describe a method for separation of the constituents of gunpowder.
Q. 62: Write down the technique used to separate.
i) The constituents of the coloring matter in ink.
ii) Hydrated copper (II) sulphate from its aqueous solution.
iii) Unused zinc, after reacting the excess with dilute sulphuric acid.
iv) Benzene (boiling point 800 C) and aniline (boiling point 1840 C).
Q. 63: A pupil decides to separate powdered calcium carbonate from powdered sodium chloride by shaking
the mixture with water and filtering. Would this procedure succeed? Explain.
Q. 64: If salt is added to water, is the mixture homogeneous or heterogeneous. Give reasons for your
Answer.