2. With Group V elements
e.g. nitrogen
This is a reversible reaction. To make
it move to the right there has to be increased
pressure (250 times the pressure of the
atmosphere) and this elevates the temperature to
500°C. A catalyst is also used. In this case the
catalyst is made from iron. The catalyst is not
changed during the reaction but it speeds up the
rate of the reaction. In this case that is
because it adsorbs the molecules of hydrogen and
nitrogen to its surface where the are closer
together and react more easily
|
 |
|
N2
+ 3H2
2NH3 |
3.
With Group VI elements e.g.
oxygen
A mixture of oxygen
gas and hydrogen gas, once ignited, will burn
easily to form water.
 |
2H2
+ O2
2H2O |
4. With
Group VII elements e.g. chlorine
The reaction
between these two gases can be explosive if there
is a lot of sunlight
 |
Cl2
+ H2
2HCl |
|