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  1. Problems
  2. /Chemical Reactions

Chemical Reactions

Chemistry
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30 problems
Type:
1.
24 g of methane burns completely: CH₄ + 2O₂ → CO₂ + 2H₂O.
High School (9–10), General · Chemical Equations, Energy Changes and CorrosionStemPy LabStemPy Lab
Hard
2.
8 g of hydrogen burns in oxygen: 2H₂ + O₂ → 2H₂O.
High School (9–10), General · Chemical Equations, Energy Changes and CorrosionStemPy LabStemPy Lab
Medium
3.
Zinc reacts with sulphuric acid: Zn + H₂SO₄ → ZnSO₄ + H₂.
High School (9–10), General · Chemical Equations, Energy Changes and CorrosionStemPy LabStemPy Lab
Medium
4.
200 g of calcium carbonate is heated until it has all broken up: CaCO₃ → CaO + CO₂.
High School (9–10), General · Chemical Equations, Energy Changes and CorrosionStemPy LabStemPy Lab
Medium
5.
What is rancidity? Give three ways to prevent it.
High School (9–10), General · Energy Changes and CorrosionStemPy LabStemPy Lab
Medium
6.
Iron pipes are galvanised: they are coated with zinc.
High School (9–10), General · Energy Changes and CorrosionStemPy LabStemPy Lab
Medium
7.
Four iron nails are kept for a week. Nail 1 is in tap water open to the air, and nail 2 is in…
High School (9–10), General · Energy Changes and CorrosionStemPy LabStemPy Lab
Easy
8.
Respiration in the cells is C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + energy.
High School (9–10), General · Energy Changes and CorrosionStemPy LabStemPy Lab
Medium
9.
5.6 g of quicklime, CaO, reacts with 200 g of water.
High School (9–10), General · Energy Changes and CorrosionStemPy LabStemPy Lab
Medium
10.
Say whether each change is exothermic or endothermic.
High School (9–10), General · Energy Changes and CorrosionStemPy LabStemPy Lab
Easy
11.
Which of these are redox reactions? Give the reason for each.
High School (9–10), General · Types of Chemical ReactionsStemPy LabStemPy Lab
Medium
12.
Name the oxidising agent and the reducing agent in each.
High School (9–10), General · Types of Chemical ReactionsStemPy LabStemPy Lab
Medium
13.
A cut apple turns brown, and a piece of iron turns reddish brown in damp air.
High School (9–10), General · Types of Chemical ReactionsStemPy LabStemPy Lab
Medium
14.
In each reaction, name the substance that is oxidised and the one that is reduced.
High School (9–10), General · Types of Chemical ReactionsStemPy LabStemPy Lab
Medium
15.
Colourless lead nitrate solution is mixed with colourless potassium iodide solution, and a bright…
High School (9–10), General · Types of Chemical ReactionsStemPy LabStemPy Lab
Medium
16.
An iron nail is kept in blue copper sulphate solution.
High School (9–10), General · Types of Chemical ReactionsStemPy LabStemPy Lab
Easy
17.
Use the reactivity series to say whether a reaction takes place.
High School (9–10), General · Types of Chemical ReactionsStemPy LabStemPy Lab
Medium
18.
Quicklime, CaO, is added to water to make slaked lime.
High School (9–10), General · Types of Chemical ReactionsStemPy LabStemPy Lab
Medium
19.
Name the kind of energy that causes each decomposition.
High School (9–10), General · Types of Chemical ReactionsStemPy LabStemPy Lab
Medium
20.
Name the type of each reaction. 2CO + O₂ → 2CO₂; 2HgO → 2Hg + O₂; Mg + CuSO₄ → MgSO₄ + Cu; KCl +…
High School (9–10), General · Types of Chemical ReactionsStemPy LabStemPy Lab
Easy
21.
Ethanol burns in a spirit lamp: C₂H₅OH + O₂ → CO₂ + H₂O.
High School (9–10), General · Chemical EquationsStemPy LabStemPy Lab
Hard
22.
Balance each equation. Keep each group of atoms together.
High School (9–10), General · Chemical EquationsStemPy LabStemPy Lab
Medium
23.
Red-hot iron reacts with steam: Fe + H₂O → Fe₃O₄ + H₂.
High School (9–10), General · Chemical EquationsStemPy LabStemPy Lab
Medium
24.
Balance each equation. K + O₂ → K₂O; H₂ + Br₂ → HBr; K + H₂O → KOH + H₂; Fe + O₂ → Fe₂O₃
High School (9–10), General · Chemical EquationsStemPy LabStemPy Lab
Easy
25.
Magnesium ribbon reacts with dilute hydrochloric acid: Mg + 2HCl → MgCl₂ + H₂.
High School (9–10), General · Chemical EquationsStemPy LabStemPy Lab
Medium
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