Question

Highly electropositive metals cannot be extracted by carbon reduction because these:

Answer 1

Hint: The oxides of very reactive metals cannot be reduced with carbon because these have more affinity for oxygen than carbon. By this approach carbon is not able to remove oxygen and hence unable to convert them to free metals.

Complete step by step answer:
First of all, what are electropositive metals? Electropositivity is defined as the tendency of an atom to donate electrons and form the positive charged cations. So, the metals that have the highest tendency to lose an electron and form a positively charged cation are known as highly electropositive metals.
For example, the univalent alkali metals ${\text{N}}{{\text{a}}^{\text{ + }}}$ and the divalent alkaline-earth metals ${\text{B}}{{\text{e}}^{{\text{2 + }}}}$.
Carbon reduction is basically the process in which the metal oxide obtained by calcination or roasting is reduced with the help of carbon. Carbon for this process is basically used in the form of coke or carbon monoxide. Carbon cannot reduce all the metals oxides to extract metals.
Highly electropositive metals cannot be extracted with the help of carbon reduction process mainly because of two reasons:
1. Metals combine with the carbon to form carbides.
2. Loss of metal is more in vaporization.
That’s why highly electropositive metals cannot be extracted with a carbon reduction process.
Option A satisfies the answer.

Note:
 Not all the metals cannot be extracted with the use of carbon reduction process, only the metals having high electropositivity cannot be extracted with this process.