Long Answer TypeWhat is the mass of hydrogen peroxide present in 1 litre of 2M solution? Calculate the volume of oxygen at STP liberated upon the complete decomposition of 100 cm3 of the above solution.
(i) To calculate the mass of H2O2 in 1 litre of 2 M solution:
Moleuclar mass of H2O2 = 2 x 1 + 2 x 16 = 34 amu
Now 1 litre of 1 M solution contains
H2O2 = 34 g
(ii) To calculate the volume of O2 liberated at STP from 1000 cm3 of 2M solution:
Decomposition of H2O2 can be represented as:
Now 68 g of 
at S.T.P. given O2 = 22400 cm3
Short Answer TypeIs demineralised or distilled water useful for drinking purposes? If not, how can it be made useful?
Multiple Choice QuestionsWhich one of the following statements about water is false?
Water can act both as an acid and as a base.
There is extensive intramolecular hydrogen bonding in the condensed phase.
Ice formed by heavy water sinks in normal water.
Ice formed by heavy water sinks in normal water.
The concentration of fluoride, lead, nitrate and iron in a water sample from an underground lake was found to be 1000 ppb, 40 ppb, 100 ppm and 0.2 ppm, respectively. This water is unsuitable for drinking due to the high concentration of:
Lead
Nitrate
Iron
Iron
From the following statements regarding H2O2, choose the incorrect statement:
It can act only as an oxidising agent
It decomposed on exposure to light
It has to be stored in plastic or wax lined glass bottles in dark
It has to be stored in plastic or wax lined glass bottles in dark
In which of the following reactions H2O2 acts as a reducing agent?
I. H2O2 + 2H+ + 2e- →2H2O
II. H2O2 - 2e- →O2 + 2H+
III. H2O2 +2e-→ 2OH-
IV. H2O2+ 2OH- -2e- →O2 + 2H2O
I and II
III and IV
I and III
I and III
Very pure hydrogen (99.9%) can be made by which of the following processes?
Mixing natural hydrocarbons of high molecular weight
Electrolysis of water
Electrolysis of water
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