determinine the limiting reagent.
determine the moles of aluminum sulfide
determine the moles of water?
are there greater then 6x moles water than aluminum sulfide? If so, aluminum sulfide is the limiting reageant.
If aluminumsulfide is the limiting reagent, then you will get three times those moles of H2S. Convert to grams.
5.00g aluminum sulfide and 10.0g water react according to the reaction:
Al2S3 + 6 H2O -> 2 Al(OH)3 + 3 H2S
What is maximum mass of H2S that can be formed?
What mass of excess reactant remains when the reaction is complete?
2 answers
This is a limiting reagent (LR) and you know that because values are given for BOTH reactants.
Al2S3 + 6 H2O -> 2 Al(OH)3 + 3 H2S
mols Al2S3 = grams/molar mass = ?
mols H2O = grams/molar mass = ?
Convert mols Al2S3 to mols H2S
Convert mols H2O to mols H2S
It is likely these two values will not agree which means one of them is not right; the correct value in LR problems is ALWAYS the smaller value and the reagent producing that value is the LR.
Now take the smaller value and convert to grams H2S. g = mols x molar mass.
Al2S3 + 6 H2O -> 2 Al(OH)3 + 3 H2S
mols Al2S3 = grams/molar mass = ?
mols H2O = grams/molar mass = ?
Convert mols Al2S3 to mols H2S
Convert mols H2O to mols H2S
It is likely these two values will not agree which means one of them is not right; the correct value in LR problems is ALWAYS the smaller value and the reagent producing that value is the LR.
Now take the smaller value and convert to grams H2S. g = mols x molar mass.