The table shows the total number of electrons in atom a and atom b.

atom number of electrons
a 10
b 12

which statement is correct?
a will give up two electrons to form bonds.
b will give up two electrons to form bonds.
both a and b will be chemically unreactive.
both a and b will gain electrons to become stable.

The correct statement is B will give up two electrons to form bonds.

Explanation:

We are given:

Number of electrons in Atom A = 10

Number of electrons in Atom B = 12

Writing the electronic configuration for both the atoms:

For A:

For B:

From the configuration, it is clearly visible that the configuration of Atom A is stable and this atom will neither gain or loose electrons to attain stability.

Atom B has 2 valence electrons and by loosing these 2 electrons, it will attain stable electronic configuration and form ion. Atom B will bond after loosing 2 electrons.

Hence, the correct statement is B will give up two electrons to form bonds.

1. they vary with a higher number because boiling is way hotter than melting

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.