Question

Question #b5376

Answer 1

`8.3997`x`10^25` atoms of `Cu`

Explanation:

1. We need to balance the equation to determine the mole ratio of `Cu` against the `Cu_3FeS_3`;
2. The balanced equation is:
   `2Cu_3FeS_3 + 7O_2 -> 6Cu = 2FeO + 6SO_2`
3. Find the formula mass of bornite, by locating the atomic masses of the elements composing the copper ore, which is equal to 344 grams per mole;
4. To start the calculation, you are provided with the mass of the raw material of `20 kg` which has 80% purity. Meaning `80%` of the raw material is bornite (copper ore). To find the mass of copper ore, multiply the mass by its purity; so that
   `20 kg`x`0.80=16 kg` of pure bornite
5. Convert the mass (kg) of pure bornite to grams to be consistent with the units being used in the formula mass; (`16,000` grams)
6. Again, `16,000` grams bornite will be converted to mole bornite by multiplying with the mole ratio reflected on the balanced equation above to arrive `139.53` mole `Cu`;
7. Since `1 mol Cu=6.02`x`10^23` atoms `Cu`, multiply the answer in step 6 by the conversion factor taken from this equaivalent statement, which is `(6.02 x 10^23 atms Cu)/(1 mol Cu)`;
8. The answer is computed as 8.3997 x `10^25` atoms `Cu`