Question

How many carbon atoms are contained in 2.8 g of c2h4 ?

Answer 1

Answer:

The answer to your question is:  1.205 x 10²³ atoms of Carbon

Explanation:

Data

Carbons atoms contained in 2.8 g C₂ H₄

MW C₂ H₄ = (12 x 2) + (4 x 1) = 24 + 4 = 28 g

                         28 g of C₂ H₄ ----------------  24 g of carbon

                         2.8 g C₂ H₄   -----------------    x

                         x = (2.8)(24) / (28)

                            = 2.4 grams of C

                             1 mol  -------------------   12 g of Carbon

                             x        -------------------    2.4 g

                            x = (2.4x 1) / 12 = 0.2 mol

                             1 mol -----------------   6.023 x 10 ²³ atoms

                           0.2 mol  --------------     x

                            x = (0.2 x 6.023 x 10 ²³) / 1

                              = 1.205 x 10²³ atoms

Answer 2

Explanation:

As molar mass of $C_{2}H_{4}$ is 28.05 g/mol and it is given that its mass is 2.8 g.

Therefore, calculate its number of moles as follows.

              No. of moles = $\frac{mass}{\text{molar mass}}$

                                    = $\frac{2.8 g}{28.05 g/mol}$

                                    = 0.099 mol

                                    = 0. 1 mol (approx)

And, according to the mole concept there are $6.022 \times 10^{23} atoms$ present in 1 mole of a substance.

Mathematically,    1 mole = $6.022 \times 10^{23}$ atoms or molecules

Therefore, calculate the number of carbon atoms present in 0.1 mol of $C_{2}H_{4}$ as follows.

              $2 \times 0.1 mol \times 6.022 \times 10^{23}}atoms /mol$

                 = $1.204 \times 10^{23}$ atoms

Thus, we can conclude that there are $1.204 \times 10^{23}$ atoms of carbon atoms present in 0.1 mol of $C_{2}H_{4}$.