Question

The molecules of metals and non-metals in the vapour state are______.
A. monatomic and polyatomic respectively
B. Polyatomic and diatomic respectively
C. Diatomic
D. Polyatomic

Answer 1

Hint:We know that there are three types of elements, metals, nonmetals and metalloids. Some examples of metals are sodium, magnesium, etc. Some examples of non-metals are oxygen, carbon, nitrogen etc and some examples of metalloids are boron, arsenic etc.

Complete step by step answer:
Metals: Metals are opaque, lustrous elements that are good conductors of heat and electricity. Most metals are malleable and ductile and are, in general, denser than the other elemental substances.
Non-metal: It is a chemical element that does not have the properties of a metal. They are not malleable and are not ductile.
Metals form cation by losing electrons. There are no definite chemical bonds between two metal atoms. They are held together by metallic bonds. There is no sharing of valence electrons between two metal atoms. Hence, they exist as in the form of monoatomic units.
Non-metals form anion (negative ions) by gaining electrons to complete their octet. Their molecules are usually polyatomic in the vapour state, such as in case of sulphur, oxygen etc.
Therefore, in vapor state metals are monoatomic and nonmetals are polyatomic.

Hence, Option (A) is the correct answer.

Additional Information:
Some of the other properties of metals are malleability, ductility, sonorous, good conductor of heat, lustrous, etc. Metals are lustrous (shining surface) in nature because of the reflection of light by free electrons. Malleability is the property of metal by which a metal can be converted into a thin sheet by hammering without being broken. Ductility is the property of metal by which stretching of metals into a wire is possible. Metals are generally called sonorous because they produce a sound when hit by a hard object. All metals are ductile and malleable except mercury as it exists in liquid state.

Note:
Generally most of the non-metals are bad conductors of electricity but graphite is one non-metal which conducts electricity because of the presence of free electrons in it. So, we can say that if free electrons are present in a metal or nonmetal it conducts electricity.