Question

Four elements A, B, C and D have the following electron arrangements in their atoms:

A	2, 8, 6
B	2, 8, 8
C	2, 8, 8, 1
D	2, 7

1. What type of bond is formed when element C combines with element D?
2. Which element is an inert gas?
3. What will be the formula of the compound between A and C?

Answer 1

1. An ionic bond is formed between element C and element D. One valence electron is completely transferred from an atom of element C to an atom of element D.
2. Element B is an inert gas. It features 8 electrons in its outermost shell, giving it a completely filled, stable valence configuration.
3. The chemical formula of the compound is C₂A. Element A (2, 8, 6) needs 2 electrons to complete its octet, while each atom of element C (2, 8, 8, 1) can lose 1 electron. Therefore, two atoms of C transfer their electrons to one atom of A. Writing the metal first yields C₂A.