(a) Name one metal which reacts with dilute hydrochloric acid to produce hydrogen gas.

(b)Name one metal which does not react with dilute hydrochloric acid.

a)In General:
Metal + Acid ---> Salt + Hydrogen Gas

Zinc metal reacts with dilute HCl to produce zinc chloride and Hydrogen gas.
Zn + 2HCl ---> ZnCl2 + H2

Test for hydrogen gas:
if we bring a burning matchstick near hydrogen gas, it burns with a pop sound.

b) The less reactive metals like Cu, Au, Ag do not react with dilute HCl acids.