In the following schematic diagram for the preparation of hydrogen gas as shown in figure, what would happens if the following changes are made?
(a) In place of zinc granules. Same amount of zinc dust is taken in the test tube.
(b) Instead of dilute sulphuric acid, dilute hydrochloric acid is taken.
(C) In place of zinc, copper turnings are taken.
(D) Sodium hydroxide is taken in place of dilute sulphuric acid and the test tube is heated.

Explanation

(a) Rate of reaction will be faster as surface area increases.
(b) No net effect will be there as both are the strong acids.
(c ) No reactions will take place as copper is less reactive than hydrogen.
(d) Zinc can also react with NaOH to give hydrogen gas.
`2NaOH+Zn to ^(Delta) Na_2ZnO_2+H_2`