Balance chemical equations
Grade 10 Science Worksheet
Circle the best answer, or write your answer on the line.
In 3 Ca(NO₃)₂, the coefficient is 3, there are 2 nitrate groups per unit and 3 oxygens per nitrate. How many oxygen atoms in all, Ari?
In 2 Al₂(SO₄)₃, the coefficient is 2, there are 3 sulfate groups per unit and 4 oxygens per sulfate. How many oxygen atoms in all, Bo?
In 3 (NH₄)₂CO₃, the coefficient is 3, there are 2 ammonium groups per unit and 4 hydrogens per ammonium. How many hydrogen atoms in all, Esme?
Which coefficients balance Mg + O₂ → MgO, Jun?
- 1, 2, 2
- 2, 1, 2
- 1, 1, 1
Which coefficients balance Na + Cl₂ → NaCl, Kira?
- 2, 2, 1
- 1, 2, 1
- 2, 1, 2
In CaCO₃ → CaO + CO₂, why can't carbonate be counted as a unit, Milo?
- Carbonate has no charge
- It breaks apart into CaO and CO₂
- Calcium is a polyatomic ion here
Why balance a polyatomic ion as one unit when it stays whole, Pia?
- It saves counting each atom
- It changes the ion's overall charge
- It adds atoms
Which is the balanced equation for calcium carbonate → calcium oxide + carbon dioxide, Ren?
- CaC → CaO + O₂
- CaCO₃ → CaO₂ + C
- CaCO₃ → CaO + CO₂
Which is the balanced equation for hydrogen + oxygen → water, Tala?
- H₂ + O₂ → H₂O₂
- H + O → HO
- 2 H₂ + O₂ → 2 H₂O
In a word equation, how is the element oxygen written, Zee?
- O₂
- O
- O₃