Test for Gases

Test for Ammonia Gas, NH3 (g)
Ammonia:
1) Has no colour.
2) Has a characteristic pungent smell.
3) Will turn moist red litmus paper blue,
and moist universal indicator paper blue.
It is alkaline in water, pH = 11.5.
4) Will put out a lit splint.


Test for Carbon Dioxide Gas, CO2(g).
Carbon dioxide:
1) Has no colour or smell.
2) Will put out a lit splint.
3) Will turn moist blue litmus paper red,
and moist universal indicator paper orange.
In water it forms carbonic acid (H2CO3), it is a weak acid (see Carbon Cycle).


Test for Chlorine Gas, Cl2(g).
Chlorine:
1) Is green-yellow in colour.
2) Has a pungent choking smell.
3) Will turn moist litmus or universal indicator paper red,
and then bleach it white.
4) Will put out a lit splint.


Test for Oxygen Gas, O2(g).
Oxygen:
1) Has no colour or smell.
2) Has no effect on moist litmus paper
or moist universal indicator paper, it is neutral.
3) Will relight a glowing splint.



Test for Hydrogen Gas, H2(g).
Hydrogen:
1) Has no colour or smell.
2) Has no effect on moist litmus paper
or moist universal indicator paper - it is neutral.
3) Burns with a characteristic 'pop'.