Questions

The letter 'P' sounds same as the vegetable 'PEA'.

Hence P is an alphabet which is a vegetable.

When atoms react they do so in order to reach the lowest energy, which is the most stable. The electrons orbitals will overlap in the way that reduces the energy the most. Orbitals of similar energy will produce the greatest stabilisation.The answer you gave isn't the whole story, it depends what species is reacting with what. The effective nuclear charge on the atom will affect the energy of the valance electrons.

Hence, the reactivity of an atom arises from the existence of unpaired electrons in the valence shell.

In message passing, it is the condition in which, both, the sender and receiver are blocked until the message is delivered.

In purifying drinking water alum is used for coagulation of mud particles.

Answer : F

Explanation :     In each group of 3 boxes, calculate the difference in numerical values between the top two letters, and add 1 to give the value of the letter in the lower box