What happens when a gas is heated in a closed metal container

When gases in containers are heated, their molecules increase in average speed. This means that they exert a greater force when they collide with the container walls, and also collide with the walls more frequently. The gas is therefore under greater pressure when its temperature is higher.

Use a magnet to separate iron, evaporate water, i'm not sure how to separate the other two i'm sorry but good luck

Answerit is not a renewable energy source;