Atomic Structure and Chemical Bonding — CHEMISTRY STD 9 — Question

Name and state the following with reference to the elements of the first three periods of the periodic table.
Noble gas with duplet arrangement of electrons.

Give reason:
Alkali and alkaline earth metal compounds usually form electrovalent compounds.

Select the odd one out and justify your answer.
Fe, Pb, Al and Zn

Identify the gases from the observations:
A colourless and odourless gas, which is neutral towards litmus. It explodes with a ‘pop” sound when a burning wooden splint is held near it.

An element A has 2 electrons in its fourth shell. State:
is it anoxidisingor reducing agent

The law which gives relationship between volume and pressure of gas at constant temperature

Identify the gases from the observations:
A colourless gas, which changes to steamy vapours on cooling. It forms colourless, tiny droplets of liquid which turn anhydrous copper sulphate blue and anhydrous cobalt chloride pink.

State: man-made sources of air pollution

What is the effect of the following pollutants on living beings?
Smoke particles

From the standpoint of atomic structure, what determines which elements will be the first and which the last in a period of the periodic table?