smoke
pruts
None, no gas is given off.
Ammonia gas (NH3) is given off when ammonia solution is heated.
hydrogen eg:Na+HCl------>NaCl+H2
Hydrogen gas is given off when magnesium reacts with sulfuric acid.
Carbon Dioxide is given off. (CO2)
Elimination of a gas produce a specific noise. Some gases are tested with a flame or with chemical reagents impregnated on special paper.
Hydrogen gas.
Oxygen gas
Hydrogen gas is always given off when an acid solution is electrolyzed.
When you place a lighted splint into, say, a test tube, where you suspect hydrogen gas is being given off, a 'pop' sound indicates the presence of the gas.
Oxygen is given of