Matter in Our Surroundings quiz

The SI unit of temperature is:

The melting point of ice is:

The process in which a solid changes directly into a gas is called:

Which state of matter has the highest compressibility?

Evaporation increases with:

300 K on the Celsius scale is:

The smell of hot food reaches us from a distance due to:

Solid carbon dioxide is called:

During the melting of ice, the temperature:

Which has the strongest force of attraction between particles?

Why does the level of water not rise when a small amount of salt is dissolved in it? (2 marks)

Why do solids have a fixed shape? (2 marks)

Why is a sponge called a solid even though it can be compressed? (2 marks)

What is the difference between evaporation and boiling? (2 marks)

Why does ice at 273 K produce more cooling than water at the same temperature? (2 marks)

Why does a desert cooler cool better on a hot dry day? (2 marks)

What is meant by the latent heat of vaporisation? (2 marks)

How does pressure help in liquefying gases? (2 marks)

Name two gases that are stored in compressed form in cylinders. (2 marks)

Why do we see water droplets on the outer surface of a glass containing ice-cold water? (2 marks)

Convert the following to kelvin: 0 degrees Celsius, 100 degrees Celsius, -40 degrees Celsius, 37 degrees Celsius. (3 marks)

The boiling point of ethanol is 78 degrees Celsius and that of water is 100 degrees Celsius. Convert both to kelvin and find the difference in kelvin. (3 marks)

A metal cube of side 2 cm has a mass of 64 g. Find its density in g per cubic cm and kg per cubic m. (3 marks)

The normal human body temperature is 37 degrees Celsius. A thermometer reads 312 K for a patient. Find the patient's temperature in degrees Celsius and how much it is above normal. (3 marks)

One atmosphere of pressure is 1.01 x 10^5 Pa. Express a pressure of 2 atmospheres and of 0.5 atmosphere in pascals. (3 marks)

Read the passage and answer the questions. In summer, people in villages store drinking water in earthen pots called matkas. The water stays cool even on hot days. (i) Why does water in a matka stay cool? (ii) Would the matka cool water better on a humid day or a dry day? Why? (iii) Give one more example of cooling by evaporation. (5 marks)

Read the passage and answer the questions. A student heats ice in a beaker and records the temperature every minute. The temperature stays at 0 degrees Celsius until all the ice melts, then rises to 100 degrees Celsius and stays there while water boils. (i) Why does the temperature stay constant while ice melts? (ii) What is the heat absorbed during boiling called? (iii) Convert 0 and 100 degrees Celsius to kelvin. (5 marks)

Read the passage and answer the questions. A few crystals of potassium permanganate were dissolved in 100 mL of water. Then 10 mL of this solution was diluted in 90 mL of clear water, and this was repeated five times. The water remained coloured. (i) What does this show about the size of particles? (ii) What does it show about the number of particles in a crystal? (iii) Why does the colour become lighter each time? (5 marks)

Read the passage and answer the questions. LPG is stored in cylinders as a liquid under high pressure. When the knob is opened, it comes out as a gas. (i) Why is LPG stored under pressure? (ii) What property of gases allows this? (iii) What happens when the pressure is released? (5 marks)

Read the passage and answer the questions. A student places camphor in a china dish, covers it with an inverted funnel and heats it gently. White fumes rise and solid camphor collects on the inner walls of the funnel. (i) Name the process. (ii) What is the reverse process called? (iii) Name one more substance that shows this. (5 marks)

Draw a labelled diagram of the interconversion of the three states of matter. Explain each process with an example. (6 marks)

Draw a labelled diagram of the experiment to determine the melting point of ice and the boiling point of water. Draw a heating curve and explain latent heat. (6 marks)

Draw diagrams showing particles in solids, liquids and gases. Compare the three states on five properties. (6 marks)

Draw a labelled diagram of an activity to show diffusion of a gas or of ink in water. Explain how temperature affects the rate of diffusion. (6 marks)

Draw a flowchart showing four factors affecting evaporation. Explain each with an example from daily life. (6 marks)