1. ❶
“JAI GURUDEV CHEMISTRY CLASSES”
// BY: - AJEET KUAMR // M.N. 7209985022
CLASS -12 TEST (Unit-07 p-block elements)
Each Question contains 3-marks
1) Though nitrogen exhibits +5 oxidation state, it does not form
pentahalide. Give reason.
2) PH3 has lower boiling point than NH3. Why?
3) Why are pentahalides more covalent than trihalides?
4) Why is BiH3 the strongest reducing agent amongst all the hydrides of
Group 15 elements?
5) Write the reaction of thermal decomposition of sodium azide.
6) Why is N2 less reactive at room temperature?
7) Why does NH3 act as a Lewis base?
8) Mention the conditions required to maximise the yield of ammonia.
9) How does ammonia react with a solution of Cu2+
?
10) What is the covalence of nitrogen in N2O5?
11) Why does NO2 dimerise?
12) Why does the reactivity of nitrogen differ from phosphorus?
13)Discuss the general characteristics of Group 15 elements with
reference to their electronic configuration, oxidation state, atomic
size, ionisation enthalpy and electro negativity. (5)
-: Complete the following reactions:-
14.NH4CI (aq) + NaNO2 (aq)
15.(NH4)2Cr2O7
16.Ba (N3)2
17.NH2CONH2 + H2O
18.NH4Cl + Ca(OH)2
19.NaNO3 + H2SO4
20.Cu + HNO3(dilute)
21.Zn + HNO3(dilute)
❷
“JAI GURUDEV CHEMISTRY CLASSES”
// BY: - AJEET KUAMR // M.N. 7209985022
CLASS -12 TEST (Unit-07 p-block elements)
Each Question contains 3-marks
1) Discuss the trends in chemical reactivity of group 15 elements.
2) Why NH3 form hydrogen bond but PH3 does not?
3) How is nitrogen prepared in the laboratory? Write the chemical
equations of the reactions involved.
4) How is ammonia manufactured industrially?
5) Illustrate how copper metal can give different products on reaction
with HNO3.
6) Why does the reactivity of nitrogen differ from phosphorus?
7) Give the resonating structures of NO2 and N2O5.
8) The HNH angle value is higher than HPH, HAsH and HSbH angles. Why?
9) Why does R3P = O exist but R3N = O does not (R = alkyl group)?
10) Explain why NH3 is basic while BiH3 is only feebly basic.
11) Nitrogen exists as diatomic molecule and phosphorus as P4. Why?
12) Why does nitrogen show catenation properties less than
phosphorus?
13) Discuss the general characteristics of Group 15 elements with
reference to their electronic configuration, oxidation state, atomic
size, ionisation enthalpy and electro negativity. (5)
-: Complete the following reactions:-
14. I2 + HNO3
15. C + HNO3
16. S8 +HNO3 (conc.)
17. P4 + HNO3 (conc.)
18. NO2 + H2O
19. NaNO3 + H2SO4
20. Cu + HNO3 (conc.)
21. Zn + HNO3 (conc.)