1. JAI GURUDEV CHEMISTRY CLASSES// BY: - AJEET KUMAR// M.N. 7209985022// f- ajeet.jha3 GROUP-16 ELMENTS
1. Why does O3 act as powerful oxidizing agent?
Ans: - Ozone decomposes rapidly to give nascent
oxygen; hence it is a good oxidizing agent.
O3 O2 + [O]
2. How is O3 estimated quantitatively?
Ans: - O3 is treated with excess of KI solution. I2 is
liberated which is titrated against a standard
solution of Na2S2O3 using starch as an indicator.
3. Comment on the nature of two S-O bonds
formed in SO2 molecule. Are the two S-O bonds in
the molecule equal?
Ans: -
4. How is the presence of SO2 detected?
Ans: - SO2 is a pungent smelling gas. It reduces
acidified orange solution of K2Cr2O7 into green,
Cr2(SO4)3.
K2Cr2O7 + H2SO4 + SO2 = Cr2(SO4)3 + K2SO4 + H2O
5. Why is Ka2 less than Ka1 for H2SO4 in water?
Ans: - Ka2 less than Ka1 for H2SO4 in water because it
is difficult to give H+
ion from HSO4
-
.
6. Compare the parameter such as bond
dissociation enthalpy, electron gain enthalpy and
hydration enthalpy, compare the oxidizing power
of F2 and Cl2.
Ans:- The electrode potential of F2 (+ 2.87 V) is
much higher than that of Cl2 (+1.3eV), therefore, F2
is much stronger oxidizing agent than Cl2.