Calculate the amount in moles and the mass in grams of KOH needed to convert 1.50 g of aluminum to KAl(OH)4. Balanced equation = 2 Al (s) + 2 KOH (aq) + 6 H2O (l)->2 KAl(OH)4 (aq) + 3 H2 (g)
You work this the same way as the alum problem I did above.
Which one ?
http://www.jiskha.com/display.cgi?id=1330564841
To calculate the amount in moles and the mass in grams of KOH needed to convert 1.50 g of aluminum to KAl(OH)4, we can follow these steps:
Step 1: Balance the equation
The balanced equation you have provided is:
2 Al (s) + 2 KOH (aq) + 6 H2O (l) -> 2 KAl(OH)4 (aq) + 3 H2 (g)
Step 2: Calculate the molar mass
Now, we need to calculate the molar mass of KOH and KAl(OH)4.
The molar mass of KOH is:
K (39.10 g/mol) + O (16.00 g/mol) + H (1.01 g/mol)
= 39.10 + 16.00 + 1.01
= 56.11 g/mol
The molar mass of KAl(OH)4 is:
K (39.10 g/mol) + Al (26.98 g/mol) + O (16.00 g/mol) + H (1.01 g/mol)
= 39.10 + 26.98 + 16.00 + (1.01 x 4)
= 39.10 + 26.98 + 16.00 + 4.04
= 86.12 g/mol
Step 3: Convert grams of aluminum to moles
To convert grams of aluminum to moles, we need to use the molar mass of aluminum, which is 26.98 g/mol.
Number of moles of aluminum = mass of aluminum / molar mass of aluminum
= 1.50 g / 26.98 g/mol
= 0.0556 mol
Step 4: Use the mole ratio
From the balanced equation, we can see that the mole ratio between KOH and aluminum is 2:2. This means that for every 2 moles of aluminum, we need 2 moles of KOH.
So, the number of moles of KOH needed is also 0.0556 mol.
Step 5: Convert moles of KOH to grams
To convert moles of KOH to grams, we use the molar mass of KOH, which is 56.11 g/mol.
Mass of KOH = number of moles of KOH x molar mass of KOH
= 0.0556 mol x 56.11 g/mol
= 3.11 g
Therefore, you would need 0.0556 moles or 3.11 grams of KOH to convert 1.50 g of aluminum to KAl(OH)4.