Aluminum reacts with sulfuric acid, which is the acid in automobile batteries. If 20.0 grams of Al is placed into a solution containing 115 grams of H2SO4, how many grams of hydrogen gas could be produced?
Please help--I do not know how to set this one up.
Thanks:)
Start by writing the equation for the chemical reaction
2 Al + 3 H2SO4 -> Al2(SO4)3 + 3 H2
Convert the masses of Al and H2SO4 to moles to find which is the limiting reactant If is is H2SO4, the number of moles of H2 formed will equal the number of H2SO4 moles present. Maybe Al is the limiting reactant. That's up to you to determine. Once you have the number of moles of H2 formed, use the fact that there are 2.016 moles of H2 per mole.
To determine the number of grams of hydrogen gas that could be produced in the reaction between aluminum (Al) and sulfuric acid (H2SO4), you need to use a balanced chemical equation for the reaction and stoichiometry.
Step 1: Write the balanced chemical equation for the reaction:
2Al + 3H2SO4 -> Al2(SO4)3 + 3H2
This equation tells us that 2 moles of aluminum react with 3 moles of sulfuric acid to produce 1 mole of aluminum sulfate (Al2(SO4)3) and 3 moles of hydrogen gas.
Step 2: Convert the mass of aluminum (Al) and sulfuric acid (H2SO4) to moles:
To convert the mass of a substance to moles, divide the mass by its molar mass. The molar mass of aluminum (Al) is 26.98 g/mol, and the molar mass of sulfuric acid (H2SO4) is 98.09 g/mol.
Moles of Al = 20.0 g / 26.98 g/mol = 0.741 mol
Moles of H2SO4 = 115 g / 98.09 g/mol = 1.173 mol
Step 3: Determine the limiting reactant:
The limiting reactant is the one that is completely consumed in the reaction and determines the amount of product that can be formed. To find the limiting reactant, compare the mole ratio of aluminum to sulfuric acid in the balanced equation.
From the balanced equation, 2 moles of aluminum react with 3 moles of sulfuric acid. Therefore, the mole ratio of Al/H2SO4 is 2/3.
If the mole ratio of Al to H2SO4 is less than 2/3, the aluminum is limiting. If it's greater than 2/3, the sulfuric acid is limiting.
Mole ratio of Al/H2SO4 = (0.741 mol Al) / (1.173 mol H2SO4) = 0.632
Since the mole ratio is less than 2/3, aluminum is the limiting reactant.
Step 4: Determine the moles of hydrogen gas produced:
Since aluminum is the limiting reactant, we can use the mole ratio from the balanced equation to determine the moles of hydrogen gas produced.
Moles of H2 = (0.741 mol Al) × (3 mol H2 / 2 mol Al) = 1.111 mol H2
Step 5: Convert moles of hydrogen gas to grams:
To convert the moles of hydrogen gas to grams, multiply the moles by the molar mass of hydrogen (H2), which is 2.016 g/mol.
Grams of H2 = 1.111 mol H2 × 2.016 g/mol = 2.239 g H2
Therefore, 2.239 grams of hydrogen gas could be produced in this reaction.