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WorksheetWise · Standard · 1097
Balancing chemical equations Work through each question. Show your reasoning where space is provided.
Name: ____________________ · Date: ____________
1. Balance using the smallest positive whole-number coefficients, including 1. Keep every chemical formula unchanged: N2 + H2 → NH3
2. Balance using the smallest positive whole-number coefficients, including 1. Keep every chemical formula unchanged: C2H6 + O2 → CO2 + H2O
3. Balance using the smallest positive whole-number coefficients, including 1. Keep every chemical formula unchanged: H2O2 → H2O + O2
4. Balance using the smallest positive whole-number coefficients, including 1. Keep every chemical formula unchanged: CH4 + O2 → CO2 + H2O
5. Balance using the smallest positive whole-number coefficients, including 1. Keep every chemical formula unchanged: H2 + O2 → H2O
WorksheetWise · en-au · 1/1 WorksheetWise · Standard · 1097
Balancing chemical equations — Answer key Work through each question. Show your reasoning where space is provided.
1. Balance using the smallest positive whole-number coefficients, including 1. Keep every chemical formula unchanged: N2 + H2 → NH3
1 N2 + 3 H2 → 2 NH3
Coefficients, in order: 1, 3, 2. Each element has the same total number of atoms on both sides.
2. Balance using the smallest positive whole-number coefficients, including 1. Keep every chemical formula unchanged: C2H6 + O2 → CO2 + H2O
2 C2H6 + 7 O2 → 4 CO2 + 6 H2O
Coefficients, in order: 2, 7, 4, 6. Each element has the same total number of atoms on both sides.
3. Balance using the smallest positive whole-number coefficients, including 1. Keep every chemical formula unchanged: H2O2 → H2O + O2
2 H2O2 → 2 H2O + 1 O2
Coefficients, in order: 2, 2, 1. Each element has the same total number of atoms on both sides.
4. Balance using the smallest positive whole-number coefficients, including 1. Keep every chemical formula unchanged: CH4 + O2 → CO2 + H2O
1 CH4 + 2 O2 → 1 CO2 + 2 H2O
Coefficients, in order: 1, 2, 1, 2. Each element has the same total number of atoms on both sides.
5. Balance using the smallest positive whole-number coefficients, including 1. Keep every chemical formula unchanged: H2 + O2 → H2O
2 H2 + 1 O2 → 2 H2O
Coefficients, in order: 2, 1, 2. Each element has the same total number of atoms on both sides.
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