Fill the gaps on group 15

Exercise and reference answers

Missing parts

1. Answer

   78

   Choices

   1. 78
   2. 21
   3. 48

2. Answer

   Chile

   Choices

   1. Chile
   2. Indian
   3. Bengal

3. Answer

   diatomic

   Choices

   1. diatomic
   2. triatomic
   3. monatomic

4. Answer

   inert

   Choices

   1. inert
   2. active
   3. noble

Complete the statement

Nitrogen makes up {0} per cent of the air. Sodium nitrate is called {1} saltpetre. Dinitrogen is a {2} gas. The plus three state gains stability from the {3} pair effect.

Instructions

Tap a word to drop it into the empty slot.

Explanation