Question

how would you show hydrogen gas is release when dil. h2so4is added to zinc granules

Answer 1

Pass the gas evolved through a soap solution and bring a burning candle near it if it burns with a pop sound then it is hydrogen gas.
Hope it helps

Answer 2

Zinc will produce hydrogen gas in reaction with dilute sulphuric acid. Because zinc is more reactive than hydrogen so it displaces hydrogen from sulphuric acid. Whereas copper is less reactive than hydrogen in activity series it placed below hydrogen .hence copper can displace hydrogen from H2SO4.