Sulfuric acid dissolves aluminum metal according to the following reaction:
2Al(s)+3H2SO4(aq)-->Al2(SO4)3(aq)+3H2(g)
Suppose you wanted to dissolve an aluminum block with a mass of 14.7 g.
What minimum mass of H2SO4(in g) would you need?
What mass of H2 gas(in g) would be produced by the complete reaction of the aluminum block?
To determine the minimum mass of H2SO4 required, we need to use the balanced equation to find the stoichiometric ratio between Al and H2SO4. The stoichiometric ratio tells us the ratio in which reactants combine to form products.
From the balanced equation, we can see that for every 2 moles of Al, we need 3 moles of H2SO4.
1. Convert the mass of Al to moles:
molar mass of Al = 26.98 g/mol
moles of Al = mass of Al / molar mass of Al = 14.7 g / 26.98 g/mol
2. Determine the moles of H2SO4 required:
moles of H2SO4 = (moles of Al) x (moles of H2SO4 / moles of Al) = (14.7 g / 26.98 g/mol) x (3 mol H2SO4 / 2 mol Al)
Now we can calculate the minimum mass of H2SO4 required:
3. Convert moles of H2SO4 to grams:
molar mass of H2SO4 = 98.09 g/mol
mass of H2SO4 = moles of H2SO4 x molar mass of H2SO4
To find the mass of H2 gas produced, we need to use the stoichiometric ratio between Al and H2 gas. From the balanced equation, we can see that for every 2 moles of Al, 3 moles of H2 gas are produced.
4. Calculate the moles of H2 gas produced:
moles of H2 gas = (moles of Al) x (moles of H2 gas / moles of Al) = (14.7 g / 26.98 g/mol) x (3 mol H2 / 2 mol Al)
5. Convert moles of H2 gas to grams:
molar mass of H2 = 2.02 g/mol
mass of H2 gas = moles of H2 gas x molar mass of H2
Therefore, the minimum mass of H2SO4 required would be the mass of H2SO4, and the mass of H2 gas produced would be the mass of H2 gas.
To determine the minimum mass of H2SO4 required to dissolve the aluminum block, we need to use stoichiometry. The balanced equation for the reaction tells us that 2 moles of aluminum react with 3 moles of H2SO4.
1. Calculate the molar mass of aluminum (Al):
The atomic mass of Al is 26.98 g/mol.
Molar mass of Al = 26.98 g/mol
2. Calculate the moles of Al:
Moles of Al = Mass of Al / Molar mass of Al
Moles of Al = 14.7 g / 26.98 g/mol
3. Use stoichiometry to find the moles of H2SO4:
According to the balanced equation, 2 moles of Al react with 3 moles of H2SO4.
Moles of H2SO4 = (Moles of Al) x (3 moles of H2SO4 / 2 moles of Al)
4. Calculate the mass of H2SO4:
Mass of H2SO4 = (Moles of H2SO4) x (Molar mass of H2SO4)
Note: You will need to look up the molar mass of H2SO4, which is 98.09 g/mol.
Mass of H2SO4 = (Moles of H2SO4) x (98.09 g/mol)
Now let's calculate the mass of H2 gas produced by the complete reaction of the aluminum block.
5. Convert the moles of Al to moles of H2 gas:
Stoichiometry tells us that 2 moles of Al react to produce 3 moles of H2 gas.
Moles of H2 gas = (Moles of Al) x (3 moles of H2 gas / 2 moles of Al)
6. Calculate the mass of H2 gas:
Mass of H2 gas = (Moles of H2 gas) x (Molar mass of H2 gas)
Note: You will need to look up the molar mass of H2, which is 2.016 g/mol.
Mass of H2 gas = (Moles of H2 gas) x (2.016 g/mol)
By following these steps, you can determine the minimum mass of H2SO4 needed and the mass of H2 gas produced by the complete reaction of the aluminum block.