Start with 3 free Unit 09 practice problems. When you want more chances to steady mole ratios, limiting reactants, theoretical yield, and percent yield, premium unlocks Quick Sets of 3, Standard Sets of 9, and Extended Sets of 18 from this 81-problem bank.
3 Free Sample Problems
Work these 3 to find out whether your stoichiometry road map is clear enough to follow without losing track — or whether the logic needs another pass before it holds up on a test.
#4Limiting Reactant
2 Mg + O2 → 2 MgO. You have 12.0 g of Mg and 16.0 g of O2. How many grams of MgO form? (MM: Mg = 24.31, O2 = 32.00, MgO = 40.30 g/mol)
#5Stoichiometry Road Map
In a stoichiometry problem, you are given grams of a reactant and asked for grams of a product. What is the correct order of conversions?
#6Percent Yield
N2 + 3H2 → 2NH3. Starting with 10.0 g N2 and 8.00 g H2, the actual yield of NH3 is 9.50 g. What is the percent yield? (MM: N2 = 28.01, H2 = 2.016, NH3 = 17.03 g/mol)
Prep for the test — not just the homework
The 3 free problems show you where you stand. The full bank is how you close the gaps before the test.
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Full worked solutions — see exactly where your setup went off track, not just whether you were right
81 problems across mole ratios, limiting reactant, theoretical yield, and percent yield
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General Chemistry · Unit 09 · Stoichiometry Practice