CBSE Class 12-science Answered

p-Block Elements

Structures of Oxoacids: phosphorus (2007), sulphur (2007),

Structures of Fluoride: sulphur (2008), xenon (2008, 2009), bromine (2009)

Interhalogen compounds (2007)

Basicity of group 15 elements (2008, 2009)

Most important topics/questions

1. Structures of PCl₅, H2SO₃, H₂SO₄, H₂S₂O₈, H₂S₂O₇, HOCl, HClO₂, HClO₃, HClO₄
2. Complete the reactions:
3. Conceptual questions:

• NF₃ is an exothermic compound whereas NCl₃ is not.
• NH₃ is a stronger base than PH₃. Why?
• Arrange the following in order of the indicated property:
  • F₂, Cl₂, Br₂, I₂ in increasing order of bond dissociation enthalpy
  • HF, HCl, HBr, HI in increasing order of acidic strength
  • NH₃, PH₃, AsH₃, SbH₃, BiH₃ in increasing order of basic strength
• What are interhalogen compounds?