Exams

The reactivity of an atom arises from the existence of unpaired electrons in the valence shell.

A cold or flu illness.

Chemical weathering is what happens when rocks are broken down and chemically altered.

Chemical weathering is the breakdown of rocks by chemical reactions. Chemical weathering involves changes in the chemical composition of the existing rock to form new rock. Some examples of chemical weathering are hydrolysis, oxidation, carbonation, dissolution, etc.

Activation energy is a minimum amount of energy that required for the chemical reaction to happen or to take place.

Complementary angles are those whose sum is 90.

Given here, is a right angled triangle, where anfle C is 90 deg. In this, sum of Angles A + C = 90, since, sum of angles in a right angled triangle = 180, angle C = 90 and

hence sum of A + B = 180 - C = 180 - 90 = 90.

Hence, the pair of cimplementary angles in the given triangle = Angle A + B.