Answer:
The answer is 6.25g.
Explanation:
First create your balanced equation. This will give you the stoich ratios needed to answer the question:
2C8H18 + 25O2 → 16CO2 + 18H2O
Remember, we need to work in terms of NUMBERS, but the question gives us MASS. Therefore the next step is to convert the mass of O2 into moles of O2 by dividing by the molar mass:
7.72 g / 16 g/mol = 0.482 mol
Now we can use the stoich ratio from the equation to determine how many moles of H2O are produced:
x mol H2O / 0.482 mol O2 = 18 H2O / 25 O2
x = 0.347 mol H2O
The question wants the mass of water, so convert moles back into mass by multiplying by the molar mass of water:
0.347 mol x 18 g/mol = 6.25g
Answer:
0.675 mol
Explanation:
Step 1: Write the balanced equation
2 Al + Fe₂O₃ ⇒ 2 Fe + Al₂O₃
Step 2: Establish the appropriate molar ratio
According to the balanced equation, the molar ratio of Fe to Al₂O₃ is 2:1.
Step 3: Calculate the moles of Al₂O₃ produced when 1.35 moles of Fe are produced
We will use the established molar ratio.
1.35 mol Fe × 1 mol Al₂O₃/2 mol Fe = 0.675 mol Al₂O₃
