• We are applying thermal energy from the Bunsen flame to the water
• This thermal energy supplied to the water leads to a gain in the INTERNAL ENERGY of the water molecules

Microwave!

• A microwave oven raises the internal energy of food by making water molecules in the food vibrate VIGOROUSLY O:

Slinky! ( So fun right)

• Potential energy is stored in the slinky as it is stretched or compressed!

MELTING AND SOLIDFICATION!

Melting is when a solid changes to a liquid upon heating
Melting occurs at a definte or constant temperature for pure substances

HOW DOES A SOLID MELT

The molecules in the solid are held by strong intermolecular bonds
The bonds have to be broken to melt
Once it is broken,the molecules can now move out of their fixed position
And therefore,A change of state from solid to liquid has occured
Hence there is no change in temperature during melting

SOLIDIFICATION!

Solidification is a reverse process of melting
Changing a LIQUID ->SOLID

Freezing point!

Water freezes to form ice at 0 degrees.
Therefore this temperature of 0 degrees is called the melting point of the water.

BOILING AND CONDENSATION

Boiling is

• A pure liquid heated and changes to a vapour

HOW ABOUT CONDENSATION?

Condensation is

• A reverse of boiling
• Changes a state from vapour to liquid
• Thermal Energy is given out during condensation

HOW DOES A LIQUID BOIL?

The thermal energy is used to do work to seperate the molecules as well as push back to the surrounding atmosphere.The molecules are now much further apart with negligible intermolecular forces of attraction btween them.

And hence when this happens boiling has taken place (YAY)