What is the name of the gas liberated when diluted hydrochloric acid is added to iron(ii)sulphide?
A. turns lime water milky B. decolorizes bromine water C. gives a pop sound D. turns lead(ii)ethanoate paper black
Correct Answer: D
Explanation
- Iron sulfide reacts with hydrochloric acid, releasing hydrogen sulfide: FeS + 2HCl → FeCl\(_2\) + H\(_2\)S. - Hydrogen sulfide reacts with lead acetate to form lead sulfide and thus produces a coloration on the paper which will vary from yellow to black, depending upon the amount of hydrogen sulfide present.