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.
Elimination of a gas produce a specific noise. Some gases are tested with a flame or with chemical reagents impregnated on special paper.
Carbon Dioxide is given off. (CO2)
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