Calculate the number of electrons present in 24 grams of carbon?

        $\mathrm{n}=\frac{\mathrm{m}}{\mathrm{M}}$
       $$\begin{gathered} \mathrm{n}=\frac{24 \mathrm{gm}}{12 \mathrm{gm}/\mathrm{mol}} \\ \mathrm{n}=2 \mathrm{moles} \end{gathered}$$

According to mole concept,

1 mole of Carbon atoms = 6.022 x 10²³ atoms of Carbon
2 moles of Carbon atoms = 2 x 6.022 x 10²³ atoms of Carbon
                                         = 12.044 x 10²³ atoms of Carbon

Now, one atom of Carbon contains 6 electrons.
So, 12.044 x 10²³ atoms of Carbon = 6 x 12.044 x 10²³ electrons of Carbon
                                                         = 72.264 x 10²³ electrons of Carbon.
                                                         = 7.23 x 10²⁴ electrons of Carbon.

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