9.1 Matter in our Surroundings

235K = _________°C

• 38

• -20

• 20

• -38

On converting 25⁰C, 38⁰C and 66⁰C to kelvin scale,the correct sequence of temperature will be

• 298 K,311 K and 339 K

• 298 K,300 K and 338 K

Latent heat of fusion is amount of

• heat energy required to change 1 kg solid into liquid completely at its melting point.

• heat energy required to convert 1 kg solid into liquid at room temperature

• heat energy required to change 1 g of solid into liquid completely

• heat energy required to change 1 kg of solid into liquid at any temperature.

Which of the following is most suitable for summer?

• Cotton

• Nylon

• Polyester

• Silk

When water gets solidified into ice, then heat is:

• absorbed

• evolved

• first absorbed then evolved

• initially evolved then absorbed

A student notices that a substance "X" has fixed volume and when transferred from one container to another, it takes the shape of that container. Identify the state of matter that substance "X" belong to:

• Liquid & gas

• Gas

• Solid

• Liquid

Density of a substance is defined as

• ratio of mass and temperature

• product of mass and volume

• ratio of mass and volume

• product of mass and temperature

which of the following is matter

• air

• stone

• cloud

• all of them

On heating, a solid is converted to liquid. This change is called

• Melting

• Fusion

• Diffusion

• Freezing

A few substances are arranged in the increasing order of ‘forces of attraction’ between their particles. Which one of the following represents a correct arrangement?

• Water, air, wind

• Air, sugar, oil

• Oxygen, water, sugar

• Salt, juice, air