CH-1 MATTER IN OUR SURROUNDINGS

Crystals of KMnO₄ in water proves that

• KMnO4 is of red colour

• KMnO4 is acidic in nature

• KMnO4 is made up of million of particles

• KMnO4 is a reducing agent

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, soil

• oxygen ,water ,sugar

• salt ,juice, air

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

Assertion(A)-Camphor disappears without leaving any residue.

Reason(R)-Camphor undergoes sublimation.

• Both A & R are true and R is the correct explanation of A.

• Both A & R are true and R is not the correct explanation of A.

• A is true but R is false.

• Both A & R are false

Assertion(A)-Liquids diffuse less easily as compared to gases

Reason(R)-Intermolecular forces are greater in gases.

• Both A & R are true and R is the correct explanation of A.

• Both A & R are false

• Both A & R are true and R is not the correct explanation of A.

• A is true but R is false

Which of the following conditions is most favourable for converting a gas into a liquid?

• High pressure, low temperature

• Low pressure, low temperature

• Low pressure, high temperature

• High pressure, high temperature

Dry ice is

• water in solid state

• water in gaseous state

• CO₂ in liquid state

• CO2 in solid state

The property of flow is unique to fluids. Which one of the following statements is correct?

• Only gases behave like fluids

• Gases and solids behave like fluids

• Gases and liquids behave like fluids

• Only liquids are fluids

Choose the correct statement of the following-

• Conversion of solid into vapours without passing through the liquid state is called sublimation.

• Conversion of vapours into solid without passing through the liquid state is called vaporisation.

• Conversion of vapours into solid without passing through the liquid state is called freezing.

• Conversion of solid into liquid is called sublimation.

When heat Is constantly supplied by a gas burner with small flame to melt Ice, Then The temperature of Ice during melting:

• Increases very slowly

• Does not increase at all

• First remains constant and then increases

• Increases to form liquid water