Answer:
25.04 g is the mass of pentane
Explanation:
Pentane density = Pentane mass / Pentane volume
1 cm³ = 1mL
0.626 g/mL = Pentane mass / Pentane volume
0.626 g/mL = Pentane mass / 40 mL
0.626 g/mL . 40 mL = Pentane mass → 25.04 g
The balanced chemical equation that illustrates this reaction is:
<span>C2H4 + 3O2 --> 2CO2 + 2H2O
</span>
From the periodic table:
mass of carbon = 12 grams
mass of hydrogen = 1 gram
Therefore:
molar mass of C2H4 = 12(2) + 4(1) = 24 + 4 = 28 grams
number of moles = mass / molar mass
number of moles of C2H4 = 54.7 / 28 = 1.95 moles
From the balanced equation above:
3 moles of oxygen are required to react with one mole of C2H4, therefore, to know the number of moles required to react with 1.95 moles of C2H4, all you have to do is cross multiplication as follows:
number of oxygen moles = (1.95*3) / 1 = 5.85 moles
