Question

(a) Among the hydrides of group 16, write the hydrides
1) which is a stronger reducing agent.
2) which has maximum bond angle.
3) which is most thermally stable.
Give suitable reason in each.
(b) complete the following equations:
S + H2SO4 (concentrated) = ?
Cl2 + Naoh (cold and dilute) = ?

Answer 1

a) Among H2O, H2S, H2Se, H2Te.

1) The strongest reducing agent is : H2Te

2) The hydride with maximum bond angle is: H2O

3) The most thermally stable hydride is: H2O

b) S + 2H2SO4 (conc) = 3SO2 + 2H2O

  Cl2 + 2NaOH (cold and dilute) = NaCl + NaClO2

• 1) As we go down the group, size of the atom increases, it becomes easier for the hydrogen to get departed.
• 2) Oxygen being smallest in group, has lone pairs more closely attached, this creates repulsions, leading to maximum bond angle.
• 3) Due to Hydrogen bonding between Oxygen and Hydrogen, the bond is more stronger, hence more thermally stable.
• Sulphur acts as reducing agent and also gets oxidized by conc. Acid.
• Chlorine gets reduced by NaOH.