Question

The atomic number of an element 'X' is 20. Write; (a) its valency,; (b) whether it is a metal or non-metal,; (c) the formula of compound formed when the element 'X' reacts with an element 'Y' of atomic number 8.; Justify your answer in each case.(All India - 2013)

Answer 1

Answer:

1- 2

2- METAL

3- XY

JUSTIFICATION-

1- AS THE ELECTRONIC CONFIG. OF THE ELEMENT IS 2,8,8,2. SO THE VALENCY WILL BE 2

2- AS IT CAN EASILY LOSE 2 ELECTRONS SO IT IS A METAL

3- THE ELECTRONIC CONFIG. OF THE ELEMENT Y WILL BE 2,6 . SO ITS VALENCY WILL BE -2

THE COMPOUND FORMED WILL BE XY

Answer 2

Answer:

1- 2

2- METAL

3- X Y

JUSTIFICATION-

1- AS THE ELECTRONIC CONFIG. OF THE ELEMENT IS 2,8,8,2. SO THE VALENCY WILL BE 2

2- AS IT CAN EASILY LOSE 2 ELECTRONS SO IT IS A METAL

3- THE ELECTRONIC CONFIG. OF THE ELEMENT Y WILL BE 2,6 . SO ITS VALENCY WILL BE -2

THE COMPOUND FORMED WILL BE XY