Raja Desing Public School

CBSE Class 9 - Science - CH1 Matter In Our Surroundings (Question Bank)

MATTER IN OUR SURROUNDINGS

Questions asked in CBSE Examination

Very Short Answer Type (1 Mark)

Q1: Expand CNG and LPG.

Q2: Which will have more impact on kinetic energy; doubling mass or doubling velocity?

Q3: Arrange the following substances in increasing order of force of attraction between the particles.

(i) milk (ii) salt (iii) oxygen

Q4: Why is sponge a solid though compressible?

Q5: Write one important characteristic of matter.

Q6: Why does a desert cooler cool better in a hot dry day?

Q7: Convert:

(a) 25°C into kelvin scale

(b) 500 K into celsius scale

Q8: Why does the smell of hot sizzling food reach you several metres away but to get the smell

from cold food you have to go close?

Q9: What is the term used for change of solid state to liquid state?

Q10: Name the temperature at which solid and liquid states of matter can coexist.

Q11: Define evaporation.

Q12: "The wool being knitted into a sweater is a physical change." Justify the statement.

Q13: Mention two ways to liquefy atmospheric gases.

Q14: What is the value of boiling point of water on Kelvin Scale of temperature?

SHORT ANSWER TYPE (2 Marks)

Q1: (a) Dry ice is compressed at high pressure. What happens when pressure is released?

(b) Suggest a method to liquefy atmospheric gases.

Q2: (a) The melting points of 2 substances A & B are 280 K and 320 K respectively. Are these substances liquid at room temperature? Justify your answer.

(b) Give an example that shows the state of matter can be changed into another state by changing the temperature.

Q3: How will you show that matter is composed of tiny particles?

Q4: Define (i) Latent heat of fusion and (ii) latent heat of vapourisation.

Q5: Explain how the following factors affect the rate of evaporation of a liquid:

(i) temperature of the liquid.

(ii) area of the exposed surface.

(iii) moisture in the surrounding air.

(iv) increase in wind speed.

Q6: When a bottle of scent is opened in one corner of a room, it immediately spreads throughout the room. What property of matter is responsible for this observation? Explain.

Q7: (a) Conversion of solid to vapour is called sublimation. Name the term used to denote the conversion of vapour to solid.

(b) Conversion of solid state to liquid state is called fusion; what is meant by latent heat of fusion?

Q8: Both boiling and evaporation convert a liquid into vapours. What is the difference between the two processes?

Q9: A sample of water under study was found to boil at 102°C at normal pressure. Is the water pure? Will this water freeze at 0°C? Comment.

SHORT ANSWER TYPE (3 Marks)

Q1: Why does the temperature of a substance remain constant during its m.pt. or boiling point?

Q2: Answer the following questions:

(i) Arrange the following substances in increasing order of force of attraction between the particles.

(i) water (ii) hydrogen (iii) sand

(ii) Why does the temperature remain constant at the melting point?

(iii) Which property of gases makes it possible to fill large volume of gases in small cylinders?

Q3: Answer the following questions:

(a) Why is ice at 273 K more effective in cooling than water at the same temperature?

(b) Name the two gases which are supplied in compressed form in homes and hospitals.

Q4: You want to wear your favourite shirt to a party but the problem is that it is still wet after a wash. What steps would you take to dry it fast?

Q5: Give reasons:

(a) Steam produces more severe burns than boiling water.

(b) We are able to sip hot tea faster from a saucer rather than from a cup.

Q6: Why do cotton clothes suit best in summer?

Q7: Classify the following into osmosis and diffusion:

(a) Swelling up of a resin on keeping in water.

(b) Spreading of virus on sneezing.

(d) Shrinking of grapes kept in thick sugar syrup.

(e) Preserving pickles in salt.

(f) Aquatic animals using oxygen dissolved in water during respiration.