#1
Which of the following is a unit of heat energy?
Joule
ExplanationBasic unit of heat energy.
#2
What is the boiling point of water in Celsius?
100°C
ExplanationTemperature at which water changes from liquid to gas.
#3
What happens to the temperature of a substance during a phase change?
It remains constant
ExplanationTemperature stays the same during phase change.
#4
Which phase change involves a substance changing directly from a solid to a gas?
Sublimation
ExplanationSolid to gas transition without passing through liquid phase.
#5
Which substance has the highest specific heat capacity?
Water
ExplanationWater can absorb a lot of heat without changing temperature much.
#6
What is the term used to describe the process of a liquid changing into a gas at the surface?
Evaporation
ExplanationLiquid turning into gas on the surface.
#7
What happens to the volume of a substance during melting?
It increases
ExplanationVolume expands during melting.
#8
What is the term used to describe the process of a gas changing into a liquid?
Condensation
ExplanationGas turning into liquid.
#9
Which law of thermodynamics states that energy cannot be created or destroyed, only transformed?
First Law
ExplanationLaw of conservation of energy.
#10
What is the term used to describe the process of a solid changing directly into a gas?
Sublimation
ExplanationSolid to gas transition without passing through liquid phase.
#11
Which substance has the highest boiling point?
Water
ExplanationWater requires high temperature to boil.
#12
What is the term used to describe the transfer of heat through direct contact between particles?
Conduction
ExplanationHeat transfer through direct contact.