Answer:
Group IA elements have only one valency electron while Group IIA have two valency electrons.
Group IA elements have cations with higher charge density hence polarizing anions easier resulting into covalent character while Group IIA elements have cations with lower charge density hence difficulty in distorting anions resulting into a ionic character. This is due to difference in cationic radii and charges
<u>Answer</u>
D. Base units
<u>Explanation</u>
Basic units are also called fundamental units. They are the standard units agreed internationally for measurements. Most of these measurements are taken from the ground and they are used to derive other units. They are seven in number. There are:
The metre (m)
The kilogram (kg)
The second (s)
The ampere (A)
The kelvin (K)
The candela (cd)
The mole (mol)
It can be stored on the land surface as ice and snow...it can seep into the earth and be stored as surface water...it can flow in the surface of lands.
An energy crisis<span> is any significant (bottleneck; logistics; or price rise) in the supply of energy resources to an economy. In popular literature, it often refers to one of the energy sources used at a certain time and place, in particular those that supply national electricity grids or those used as fuel in vehicles.</span>