Topic 5 Changing State

What is the biggest difference between these two pictures of Edmonton? Because it is hot in the summer and cold in the winter we already know that temperatures are always changing…

Snow. What happens to the snow when it gets warmer

What is happening to the particles when water melts?

They gain energy, move faster, and break free of their shape.

Liquid to a gas When we add even MORE heat… The particles move VERY fast and escape all bonds!

Different Materials Different materials expand by different amounts when they are heated. The amount the temperature rises when thermal energy is added also depends on the substance. Under identical conditions, materials warm and cool at different rates.

Temperature and Thermal Energy Two substances may have the same amount of thermal energy but have different temperatures. Scientists use 2 properties to determine how fast something will warm up Heat Capacity Specific Heat Capacity

Heat Capacity The amount of thermal energy that warms or cools the object by one degree Celsius. Describes a particular object Depends on the mass of the object and the material the object is made of

Specific Heat Capacity The amount of thermal energy that warms or cools one gram of a material by one degree Celsius. Describes a particular material Depends on the material the object is made of.

Definitions Melt: Turn from solid ice to liquid water Freeze: Turn from liquid water to ice Evaporate: turn into invisible water vapour Condense: Turn back from gas to liquid water Melting Point: The temperature at which a solid turns into a liquid Boiling Point: The temperature at which a liquid turns into a gas.

What is sublimation? From solid to gas in one step…

Most of the time we go from a solid  liquid  then to a gas. This happens because we are adding ENERGY In sublimation we go through this process very fast and go from Solid  Gas