Which of the
following gas is produced during the decomposition of lime stone into lime
(calcium oxide)?
a) nitrogen
b) hydrogen
c) carbon dioxide
d) oxygen
Commercially sodium is obtained from which of the following molten salt?
a) Na2CO3
b) NaCl
c) NaO
d) NaHCO3
Which of the following type of reaction takes when electricity is passed through molten NaCl, and produce sodium and chlorine?
a) combustion
b) displacement
c) double-displacement
d) decomposition
A chemical reaction in which a more reactive element takes the place of a less reactive element in a compound is called ……reaction.
a) burning
b) displacement
c) double-displacement
d) addition
Which of the
following reaction show displacement reaction?
a) C(s) + O2(g) ------à CO2(g)
b) Zn(s) + H2SO4(aq)
-----à ZnSO4(aq) + H2(g)
c) 4Ag(s) + O2(g) ------à 2Ag2O(s)
d) 2Ca(s) + O2(g)------à
2CaO(s)
Iron can be extracted from iron oxide by heating with…….
a) water
b) hydrogen
c) oxygen
d) coke (carbon)
