Question

Q. Define an atom. An atom 'X' of an element has electronic configuration 2, 8, 2.
Write the following information about the element:
a) Atomic number of X
b) Valence electron
c) Valency
d) Is X' metal or non-metal​

Answer 1

Answer:

An atom is the smallest unit of matter taking part in a chemical reaction.

a) the atomic no of X is 2+8+2 .i.e.12

b)2, it is the number of electrons in the last or Valence shell that is 2 here

3)2+ , since here X has to lose 2 electrons to become stable

4)X is a metal because it loses 2 electrons to become stable

NOTE: AN ELEMENTS WHICH LOSE ELECTRONS ARE METALS AND WHICH GAIN ARE NON METALS

Answer 2

Answer:

Atom = atom is a smallest particle of an element.

a) Atomic number of X is 12

b) Valence electron is 2

c) Valency is +2

d) X is metal

( X is magnesium atom )