Share CHEMISTRY CH 1
Save to Folder
The process of changing a substance from a solid to a liquid state is called: a) Melting b) Freezing c) Evaporation d) Condensation
Melting
The temperature at which a substance changes from a liquid to a gas is called: a) Boiling point b) Melting point c) Freezing point d) Condensation point
a) Boiling point
Which of the following is not a physical change? a) Boiling of water b) Rusting of iron c) Melting of ice d) Dissolving sugar in water
b) Rusting of iron
Which of the following has heighest kinetic energy? (a) Particles of ice at 0 °C(b) Particles of water at 0 °C (c) Particles of water at 100 °C(d) Particles of steam at 100 °C
(d) Particles of steam at 100 °C
Which of the following is most suitable for summer? (a) Cotton(b) Nylon(c) Polyester(d) Silk.
(a) Cotton
Which of the following does not affect rate of evaporation? (a) Wind speed(b) Surface area (c) Temperature(d) Insoluble heavy impurities
(d) Insoluble heavy impurities
Which one of the following sets of phenomena would increase on raising the temperature? (a) Diffusion, evaporation, compression of gasesNCERT Books (b) Evaporation, compression of gases, solubility (c) Evaporation, diffusion, expansion of g
(c) Rate of evaporation, diffusion and expansion of gases increase with increase in temperature.
The property to flow is unique to fluids. Which one of the following statements is correct? (a) Only gases behave like fluids. (b) Gases and solids behave like fluids. (c) Gases and liquids behave like fluids. (d) Only liquids are fluids.
(c) Gases and liquids behave like fluids.
During summer, water kept in an earthen pot becomes cool because of the phenomenon of (a) diffusion (b) transpiration (c) osmosis (d) evaporation.
d) Earthen pot has small pores through which water keeps evaporating and evaporation causes cooling.
Which of the following is not a pure substance? a) Water b) Air c) Diamond d) Gold
b) Air
Which of the following is a homogeneous mixture? a) Orange juice with pulp b) Sand and water c) Saltwater d) Oil and vinegar
Answer: c) Saltwater
Which of the following statements is true about a solution? a) It is a heterogeneous mixture. b) It contains only solute. c) It has a fixed composition. d) It cannot be separated by physical methods.
Answer: c) It has a fixed composition.
Which of the following is a compound? a) Air b) Carbon c) Saltwater d) Soil
Answer: c) Saltwater
Which of the following is a heterogeneous mixture? a) Vinegar b) Milk c) Soda water d) Air
Answer: b) Milk
Which of the following is an example of a pure substance? a) Sea water b) Sand c) Oxygen gas d) Colored candy
Answer: c) Oxygen gas
Which of the following is a mixture? a) Hydrogen gas b) Copper wire c) Brass d) Sodium chloride (table salt)
Answer: c) Brass
