The graph below shows how the temperature changes when energy in the form of heat is added to 1 g of water.
heating curve 1 g water 400 by 250 no colours
This graph shows that
addition of heat at the
boiling and melting temperature of water does
not cause a
temperature change.
Heat added at the
melting temperature of ice causes any
ice that is present to be
converted to liquid
water.
The temperature does not rise until ALL of the ice present is converted to liquid water.
Heat added at the
boiling temperature causes any liquid
water that is present to be converted to
steam.
The temperature does not rise until ALL of the liquid water present is converted to water vapour (gas).
The term steam is commonly used to refer to gaseous water.. Steam is actually a fog of water droplets in water vapour.
Water vapour is a colourless gas, and you can not see water vapour mixed with air. What you can see in steam is the droplets of water.