Stem react with
red-hot iron to form the magnetic…………..
a) nitrogen oxide
b) iron
oxide
c) carbon dioxide
d) zinc oxide
The chemical formula of calcium hydroxide is…………
a) Ca(OH)2
b) CaO
c) NaOH
d) CaCO3
Metals such as ……do not react with water at ordinary condition.
a) Cu
b) Hg
c) Au
d) all of these
The symbol of mercury is ………….
a) Hg
b) Au
c) Ag
d) Pt
Chlorine gas reacts with water to produce…..
a) hydrochloric acid
b) hypochlorous acid
c) both a & b
d) none of these
The general formula of hypochorous acid is…
a) HCl
b)HOCl
c) 2HCl
d) NaOH
