NTA Abhyas JEE Main2020Chemistrys Block ElementsPractice
Which of the following metal pairs on burning in moist air do not give smell of ammonia? Mg, Ca, K, Li, Na, Al
Options
- AMg, K
- BCa, Na
- CK, Na
- DLi, Al
Correct answer
C. K, Na
Step-by-step solution
Mg + N 2 → Mg 3 N 2 → moist H 2 O Mg OH 2 + NH 3 Ca + N 2 → Ca 3 N 2 → moist H 2 O Ca OH 2 + NH 3 Li + N 2 → Li 3 N → moist H 2 O LiOH + NH 3 K + N 2 → no reaction N a + N 2 → no reaction Hence, Sodium and Potassium do not give smell of ammonia.