Questions

Flourine is the most electro negative element due to its small atomic radius .It also has the tendency to accept an electron to complete octet configuration

In the given puzzle,

The logic is in the format of lets say, a/b

In that case b doesn't matter, because

2/2 = 1,

6/5 = 6/2 = 3,

10/11 = 10/2 = 5

This means that equation is a/2

So 16/19 is equal 16/2 = 8.

Allotropes are the different physical forms of an element. Here in the given options, diamond and graphite are the pair of allotropes of carbon.

Some more examples are Molecular oxygen and ozone are pair of allotropes, Black and red phosphorous are also pairs of allotropes.