Question

The atomic number of four elements p,q,r,s are 6,10,12,17 respectively which two elements can combine to form a covalent compound

Answer 1

Here, p, q, r, s, are, atomic no. 6,10,12,17 respectively.

So, we can conclude that

p = carbon

q= neon

r= magnesium

s= chlorine

(I) We know neon is a noble gas, it will neither react nor form any sort of bond.

So, we can take it out of the picture.

(Il) Now, magnesium is an alkali earth metal having high tendency to donate electrons.

It is less likely to form a covalent bond.

(Ill) carbon and chlorine are both non metals, hence have a tendency to form

covalent bonds.

Also Electronegativity difference between them is not high i.e. EN of C =2.5 and EN of Chlorine = 3

Hence, the probability of formation of an ionic bond is low and that of formation of covalent bond is high.

(IV) p and s will form a covalent bond

Example:- CCl4 carbontetrachloride

Answer 2

The covalent compound will be formed between Carbon and Chlorine.

Thus the resultant compound will be CCl4 i.e. Carbon tetra-chloride.

Explanation:

Let's say 6, 10, 12 and 17 are C, Ne, Mg and Cl respectively.

Now we know that

Carbon = 6

Neon = 10

Magnesium = 12

Chlorine = 17

• Let's start with Noble gas. As Neon is a noble gas and its electronic configuration shows that its octet is complete so it is an inert gas.
• Then magnesium is an alkali metal it has the tendency to donate electron easily because it is an electro-positive metal.
• Then Chlorine and carbon both are non-metals and have the tendency to form covalent bond through sharing of electron. The less electro-negative difference between them i.e 0.5 enable them to form a covalent cmpound.
• Thus the resultant compound will be CCl4 i.e. Carbon Tetrachloride.