Question

For the reaction C + 2H2 → CH4, how many grams of carbon are required to produce 7.8 moles of methane, CH4 ?

Round your answer to the nearest tenth. If you answer is a whole number like 4, report the answer as 4.0

Use the following molar masses. If you do not use these masses, the computer will mark your answer incorrect.:

Element Molar Mass
Hydrogen 1
Carbon 12

Answer 1

The balanced chemical equation for the reaction is:

C + 2H2 → CH4

From the equation, we can see that 1 mole of carbon reacts with 2 moles of hydrogen to produce 1 mole of methane. Therefore, to produce 7.8 moles of methane, we would need:

1 mole of carbon = 1 mole of CH4 / 2 moles of H2 = 1/2 mole of CH4

7.8 moles of CH4 = 7.8 × (1/2) moles of C = 3.9 moles of C

Now, we can use the molar mass of carbon to convert moles to grams:

Atomic mass of carbon (C) = 12.01 g/mol

3.9 moles of C × 12.01 g/mol = 46.8 g of C

Therefore, we need 46.8 grams of carbon to produce 7.8 moles of methane (CH4). Rounded to the nearest tenth, the answer is 46.8 grams.