If 45.3 grams of aluminum react with an excess of oxygen, as shown in the balanced chemical equation below, how many grams of aluminum oxide can be formed?
4Al + 3O2 2Al2O3
Follow the steps in this example.
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1. 4Al + 3O2 = 2Al2O3
2. Set the equation. mol ratio is 4:2
45.3 g Al * (1 mol Al / 26.982 g Al) * (2 mol AlO / 4 mol Al) * (101.964 g AlO / 1 mol AlO)
= 85.63 g Al2O3
To find out how many grams of aluminum oxide can be formed, we need to use the molar ratio in the balanced equation.
The molar ratio between aluminum (Al) and aluminum oxide (Al2O3) is 4:2, or simplified, 2:1. This means that for every 2 moles of aluminum, we will get 1 mole of aluminum oxide.
To calculate the amount of aluminum oxide formed, we need to convert the given mass of aluminum (45.3 grams) to moles.
The molar mass of aluminum (Al) is 26.98 grams/mole.
Using the following equation:
moles = mass / molar mass,
we can calculate:
moles of aluminum = 45.3 grams / 26.98 grams/mole.
This gives us the number of moles of aluminum.
Now, since the molar ratio of Al2O3 to Al is 1:2, we can multiply the moles of aluminum by 2 to find the moles of aluminum oxide.
Finally, we convert the moles of aluminum oxide back into grams using the molar mass of aluminum oxide.
The molar mass of aluminum oxide (Al2O3) is:
2(26.98 g/mole Al) + 3(16.00 g/mole O) = 101.96 g/mole.
We multiply the moles of aluminum oxide by the molar mass to find the grams of Al2O3.
To find how many grams of aluminum oxide can be formed, you need to use the molar ratios from the balanced chemical equation.
According to the equation, 4 moles of aluminum react with 3 moles of oxygen to produce 2 moles of aluminum oxide.
To calculate the number of moles of aluminum, you need to use the molar mass of aluminum, which is 26.98 grams/mole.
The formula to calculate the moles is:
moles = mass / molar mass
Therefore, the number of moles of aluminum is:
moles of aluminum = 45.3 grams / 26.98 grams/mole
Calculating this, you get:
moles of aluminum = 1.6792 moles
Now, using the molar ratios from the balanced equation, you can determine the number of moles of aluminum oxide formed. Since the ratio between aluminum and aluminum oxide is 4:2, you divide the number of moles of aluminum by 4 and multiply it by 2:
moles of aluminum oxide = (moles of aluminum / 4) * 2
Substituting the value of moles of aluminum, you get:
moles of aluminum oxide = (1.6792 moles / 4) * 2
Calculating this, you get:
moles of aluminum oxide = 0.8396 moles
Now, to find the mass of aluminum oxide, you need to multiply the number of moles by the molar mass of aluminum oxide. The molar mass of aluminum oxide is the sum of the molar masses of two aluminum atoms (2 x 26.98 grams/mole) and three oxygen atoms (3 x 16 grams/mole):
molar mass of aluminum oxide = (2 x 26.98 grams/mole) + (3 x 16 grams/mole)
Calculating this, you get:
molar mass of aluminum oxide = 101.96 grams/mole
Finally, to calculate the mass of aluminum oxide formed, you multiply the number of moles by the molar mass:
mass of aluminum oxide = moles of aluminum oxide * molar mass of aluminum oxide
Substituting the value of moles of aluminum oxide, you get:
mass of aluminum oxide = 0.8396 moles * 101.96 grams/mole
Calculating this, you get:
mass of aluminum oxide ≈ 85.71 grams
Therefore, approximately 85.71 grams of aluminum oxide can be formed.