Atomic Structure and Chemical Bonding — CHEMISTRY STD 9 — Question

The electronic configuration of nitrogen is (2, 5). How many electrons in the outer shell of a nitrogen atom are not involved in the formation of a nitrogen molecule?

Identify the gases from the observations:
A greenish yellow gas having a pungent and suffocating smell. It turns moist blue litmus paper red and then bleaches it.

Define the term:
Ion

Name two compounds that are covalent when taken pure but produce ions when dissolved in water.

Give the impact of acid rain: On water bodies

Hydrogen may be prepared in the laboratory by the action of a metal on an acid.
How would you modify your apparatus to collect dry hydrogen? Which drying agent would you employ for this purpose?

Name an element which does not contain neutron.

Which group of elements was missing from Mendeleev's original periodic table?

Give reason:
Alkali metals and halogens do not occur free in nature.