Last lesson we calculated that propane has an energy of combustion of 2220 kilojoules per mole while hydrogen gas (rocket fuel)
has an energy of combustion of 286 kilojoules per mole. However, hydrogen gas has a much higher energy of combustion per gram than propane. Why is this? 
1 answer:
You might be interested in
Answer:
4.18 g
Explanation:
The formula for the calculation of moles is shown below:
Given: For Li
Given mass = 2.50 g
Molar mass of Li = 6.94 g/mol
<u>Moles of Li = 2.50 g / 6.94 g/mol = 0.3602 moles</u>
Given: For
Given mass = 2.50 g
Molar mass of = 28.02 g/mol
<u>Moles of = 2.50 g / 28.02 g/mol = 0.08924 moles</u>
According to the given reaction:
6 moles of Li react with 1 mole of
1 mole of Li react with 1/6 mole of
0.3602 mole of Li react with mole of
Moles of that will react = 0.06 moles
Available moles of = 0.08924 moles
is in large excess. (0.08924 > 0.06)
Limiting reagent is the one which is present in small amount. Thus,
Li is limiting reagent.
The formation of the product is governed by the limiting reagent. So,
6 moles of Li gives 2 mole of
1 mole of Li gives 2/6 mole of
0.3602 mole of Li react with mole of
Moles of = 0.12
Molar mass of = 34.83 g/mol
Mass of = Moles × Molar mass = 0.12 × 34.83 g = 4.18 g
<u>Theoretical yield = 4.18 g</u>