CBSE
Multiple Choice QuestionsThe most probable velocity (in cm/s) of hydrogen molecule at 27C will be
19.3 x 104
17.8 x 104
24.93 x 109
17.8 x 108
H2O is liquid while H2S is a gas due to
covalent bonding
molecular attraction
H-bonding
both H-bonding and molecular attraction
For binary hydrides of formula M x n the value of n can be fractional for:
salt like hydrides
interstitial hydrides
covalent hydrides
polymeric hydrides
The reaction of HBr with 
in the presence of peroxide will give
CH3CH2CH2CH2Br
Presence of phosphoric acid or glycerine or acetanilide retards the decomposition of H2O2 .This is an example of:
Positive catalysis.
Negative catalysis.
Auto catalysis.
Induced catalysis.
Hydrogen peroxide when added to a solution of potassium permangnate acidified with sulphuric acid:
Acts as an oxidising agent
Acts as a reducing agent
Forms water only
Forms water only
The oxide that gives H2O2 on treatment with dilute acid is
PbO2
MnO2
Na2O2
TiO2
The number of moles of oxygen obtained by the electrolytic decomposition of 108 g water is
2.5
3
5
7.5
Hardness of water is due to presence of salts of:
Na+ and K+
Ca2+ and Mg2+
Ca2+ and K+
Ca2+ and Na+
Heavy water is
CaSO4
water contain CaSO4, MgSO4
D2O
water contain CaCO3
