Question

The electronic configuration of three elements X, Y and Z are as follows:
X = 2, 4, Y = 2, 7, Z = 2,1 Which two elements will combine to form an ionic compound and write the correct formula,
(a) X2Y
(b) YZ
(c) XZ3
(d) Y2Z

Answer 1

Given:

Electronic configuration of:

Element X = 2,4

Element Y =2,7

Element Z = 2,1

To Find:

Which two elements will combine to form an ionic compound

Solution:

What is an ionic compound?

• A compound consisting of "positively and negatively charged particles held together by the electrostatic force of attraction is called an ionic compound".
• The compound is neutral.

How is an ionic compound formed?

• An ionic compound is formed when an element loses an electron(s) to an element that can accept it.
• Thus, we need an electropositive metal (donor atom) and an electronegative metal (acceptor atom).

• In the given question, let us analyze each element.

1. Element X

• It has 4 valence electrons.
• Thus it needs to either lose or accept 4 electrons to form an octet.
• This would require a large amount of ionization energy, hence it may not be energetically feasible.

2. Element Y

• It has 7 valence electrons.
• It needs only 1 more electron to complete its octet, hence it is an electronegative element.

3. Element Z

• It has 1 valence electron.
• If it loses 1 electron, it will attain the stable configuration of 2 electrons in the 1st shell.
• Thus, it is an electropositive element.

So, we can see that Y and Z can meet each other's requirements as Z can donate an electron to Y.

                      ⇒ Z → Z⁺ + e⁻  

                and  Y + e⁻ → Y⁻

                      ⇒Y⁻ + Z⁺ → YZ

Hence, YZ is an ionic compound.

So, option (b) YZ is correct.

Answer 2

Explanation:

(b) YZ is the answer of the following question