Question

How many grams of H2 would be formed if 34 grams of carbon reacted with an unlimited amount of H2O? The reaction is:

C + H2O → CO + H2

The atomic mass of C is 12.01 g/mole. The atomic mass of H2 is 2.016 g/mole. Finish the problem by choosing the correct format for dimensional analysis.

Answer 1

Answer : The mass of
`H_2` will be, 5.66 grams

Explanation : Given,

Mass of C = 34 g

Molar mass of C = 12 g/mole

Molar mass of
`H_2` = 2 g/mole

First we have to calculate the moles of carbon.

`\text{Moles of }C=\frac{\text{Mass of }C}{\text{Molar mass of }C}=(34g)/(12g/mole)=2.83mole`

Now we have to calculate the moles of
`H_2`.

The given balanced chemical reaction is,

`C+H_2O\rightarrow CO+H_2`

From the balanced reaction, we conclude that

As, 1 mole of C react to give 1 mole of
`H_2`

So, 2.83 mole of C react to give 2.83 mole of
`H_2`

Now we have to calculate the mass of
`H_2`.

`\text{Mass of }H_2=\text{Moles of }H_2* \text{Molar mass of }H_2=2.83mole* 2=5.66g`

Therefore, the mass of
`H_2` will be, 5.66 grams

Answer 2

Equation:
C + H2O → CO + H2
1mol C produces 1 mol H2
Molar mass Co = 12.01g/mol
mol C in 34g = 34/12.01 = 2.831 mol of C
This will produce 2.831 mol H2
Molar mass H2 = 2016 g/mol
Mass of 2.831 mol H2 = 2.831 * 2.016 = 5.7072g H2 produced
Answer must have 2 significant figures: Mass H2 = 5.7g