You know oxygen is the limiting reactant (since it says there is excess hydrogen). So, use stoichiometry based on the given number of oxygen moles:
Answer:
The mass is 0.855 grams (option A)
Explanation:
Step 1: Data given
aluminium sulfate = Al2(SO4)3
Numer of moles Al2(SO4)3 = 2.50 * 10^-3 moles
atomic mass Al = 26.99 g/mol
atomic mass S = 32.065 g/mol
Atomic mass O = 16 g/mol
Step 2: Calculate molar mass Al2(SO4)3
Molar mass = 2* 26.99 + 3*32.065 + 12*16
Molar mas = 342.175 g/mol
Step 3: Calculate mass Al2(SO4)3
Mass Al2(SO4)3 = moles Al2(SO4)3 * molar mass Al2(SO4)3
Mass Al2(SO4)3 = 2.5 *10^-3 moles * 342.175 g/mol
Mass Al2(SO4)3 = 0.855 grams
The mass is 0.855 grams (option A)
Yeah what is the question
