CH-1: Matter in our surroundings Class 9

Which of the following is not a property of solids-

• Rigidity

• Fluidity

• Definite shape

• Definite volume

Evaporation is-

• Directly proportional to humidity

• Inversely proportional to humidity

• Directly proportional to temperature

• Inversely proportional to temperature

A change of state directly from solid to gas without into liquid state is called-

• Deposition

• Vaporization

• Sublimation

• Evaporation

Convert 300K into Celsius scale-

(a)  

Which of the following are factors of evaporation ?

• Humidity

• Wind speed

• Condensation

• Increase in surface area

Fusion is-

• The process of melting of solid state into liquid state.

• The minimum temperature at which a solid melts to become a liquid at atmospheric temperature

• When the vapor pressure equalizes the atmospheric pressure

• Particles of higher concentration move to lower concentration

Gases can be liquefied by-

(a)  

Bose Einstein condensate was first calculated in-

• 1920

• 1915

• 1914

• 1949

The physical state of water at 250degree Celsius is-

(a)  

S.I unit of density is-

(a)