(a) Define the term mole. (b) If 1 g of carbon contains x atoms, what will be the number of atoms

(a) Mole : A mole of a substance is that amount of the substance which contains the same number of particles (atoms, molecules or ions) as there are carbon atoms in 12 g of carbon - 12 element.

(b) 1 mole of carbon = Gram Atomic Mass of carbon = 12 g

So, 1 of carbon =1/12 = mole of carbon

1 mole of an element = 6.023 × 10²³ atoms of element  

1/12 mole of carbon = 6.023 × 10²³   x 1/12 atoms = x

Now, 1 mole of magnesium= Gram Atomic Mass of magnesium = 24 g

So, 1 g of Magnesium m=1/24  mole of magnesium.

1 mole of magnesium contain = 6.023 × 10²³ atoms

1/24 mole of magnesium contain =1/24× 0.023 × 10²³ atoms

According to the questions -

1/12 x 6.023 x 10²³  carbon atoms = x

1/24 x  6.023 x 10²³ magnesium atoms x/2

1 g of magnesium contains x/2 atoms.

Thus, if 1 gram of carbon contains x atoms, then 1 gram of magnesium will have x/2  atoms in it.