A metal which cannot be used for preparation of hydrogen using dilute acids

• Zn

• Fe

• Pb

• Cu

An acid which can not give hydrogen gas with metal

• Sulphuric acid

• Hydrochloric acid

• Nitric acid

• Carbonic acid

Metal which sink into water first then float

• Na

• K

• Cu

• Ca

The element placed below hydrogen in group 1

• Na

• Li

• K

• F

The element other than hydrogen which forms a molecule containing a single covalent bond

• Cl

• N

• O

The element which like hydrogen has one valence electron

• He

• Na

• F

• O

The element which like hydrogen is a strong reducing agent

• Pb

• Na

• S

• Cl

The element which forms a diatomic molecule

• C

• Br

• S

• P

Metal which can give hydrogen gas even with nitric acid

• Ca

• Mg

• Na

• K

Granulated zinc is preferred over other metals because it

• contains copper which acts a catalyst

• contains iron

• none