Question

Calculate the number of carbon atoms contained in 5.6 g of C2H4

Answer 1

Molecular mass of C₂H₄ is,

M = 2×12 + 4×1 g/mol

M = 28 g/mol

Moles of C₂H₄ in 5.6 g of C₂H₄ :

n = 5.6/28 mol

n = 0.2 mol

Now, 1 mol of C₂H₄ contains 2 moles of carbon.

So, number of moles of carbon are :

n = 0.4 mol

We know, 1 mol of any atom contains 6.022 × 10²³ atoms.

So, number of carbon atoms are :

$N = 0.4 \times 6.022\times 10^{23} \\\\N = 2.409 \times 10^{23}$

Hence, this is the required solution.