It depends of the concentration and of the sulfuric acid and possibly the concentration and the volume of the NaCl. 1. IF you use 98% H2SO4 and anhydrous NaCl, You will get huge, corrosive, white fumes of HCl gas being produced. read more
If the acid is concentrated sulphuric acid you’ll get a reaction and hydrogen chloride gas will be given off - nasty stuff if you smell it. It dissolves in the moisture in your nose making hydrochloric acid - feels like a needle was shoved up your nose. read more
Magnesium readily reacts with sulfuric acid and forms hydrogen gas bubbles and aqueous magnesium sulfate after the reactants are consumed. The easiest way to see this reaction is to take a test tube of sulfuric acid and drop a small ribbon of magnesium into the clear liquid. read more
The products will be a mix of sodium bisulfate and sodium sulfate, depending on the relative amounts of the reactants. Hydrogen chloride gas will be produced. Word equation: Solid sodium chloride plus liquid sulfuric acid produces solid sodium sulfate plus hydrogen chloride gas. read more