Gases in Gasfitting Lesson

States of Matter

All substances are made up of molecules.

In solids the molecules are tightly packed together and do not move around easily.

In liquids, molecules have more room between them so they move and take shape of any container into which they are put.

In a gas, the molecules have a lot more room to move around freely and quickly. These molecules are constantly bumping into each other and their containment.

This bumping and bouncing around creates the pressure we get inside our gas pipes. Because the molecules move in all directions, they create an equal pressure on any container in which they are enclosed.

Gases must be kept in a completely  sealed 'gas tight' container or they will disperse into the surrounding atmosphere

Gas Characteristics

Each gas has different characteristics.

• Some are heavier than others. Which is called specific gravity, and measured compared to air.
• Some gases are able to be burnt and some are inert (will not burn).
• Gases which burn produce different amounts of energy when burnt.

The gases used in Gasfitting in New Zealand (Methane, Butane and Propane) are part of the Hydrocarbon family. 

These are made up of Hydrogen and Carbon atoms, each gas has its own different mix.

For example Methane (Natural Gas) is : CH4 which is 4 parts Hydrogen to 1 part Carbon