Answer:
Explanation:
Our 
sample yielded 1g of 
and 16g of 
, but our unknown sample yielded 2 times as much for the same amount of .
What does this mean? that the H:O proportion for the unknown sample is twice the H:O proportion for the sample.
What is the H:O proportion for the sample? As we can see from its formula, it's 1:1, therefore the proportion for the unknown formula must be 2:1.
That means, two H atoms for every O atom. We could write that as: 
and you should recognize that formula, for it is one of the most common compounds on earth, Water.
Answer:
There are 1.51 x 1024 molecules of carbon dioxide in 2.50 moles of carbon dioxide.
Explanation:
Answer:
0.733 mol.
Explanation:
- From the balanced equation:
<em>2Fe₂O₃ + C → Fe + 3CO₂,</em>
It is clear that 1.0 moles of Fe₂O₃ react with 1.0 mole of C to produce 1.0 mole of Fe and 3.0 moles of CO₂.
- Since Fe₂O₃ is in excess, C will be the limiting reactant.
<u><em>Using cross multiplication:</em></u>
1.0 mole of C produces → 3.0 moles of CO₂, from the stichiometry.
??? mole of C produces → 2.2 moles of CO₂.
∴ The no. of moles of C needed to produce 2.2 moles of CO₂ = (1.0 mole of C) (2.2 mole of CO₂) / (3.0 mole of CO₂) = 0.733 mol.
