Decomposition Reactions
Chemistry ⇒ Chemical Reactions and Equations
Decomposition Reactions starts at 9 and continues till grade 12.
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A student heats a sample of potassium chlorate and collects a gas that relights a glowing splint. Name the gas and write the balanced equation for the reaction.
A white solid turns yellow on heating and returns to white on cooling. Name the compound and the type of reaction.
Explain why decomposition reactions are important in the environment.
Explain why decomposition reactions are usually endothermic.
A student heats a sample of potassium chlorate and collects a gas that relights a glowing splint. Name the gas and write the balanced equation for the reaction.
A white solid turns yellow on heating and returns to white on cooling. Name the compound and the type of reaction.
Calculate the number of moles of oxygen gas produced when 0.5 moles of potassium chlorate decompose completely. (2KClO3 → 2KCl + 3O2)
State whether the following reaction is a decomposition reaction:
2H2O (l) → 2H2 (g) + O2 (g)
Which of the following is a characteristic of decomposition reactions?
(1) They always release energy.
(2) They involve the breakdown of a single compound.
(3) They always require a catalyst.
(4) They form a single product.
Which of the following is a decomposition reaction?
(1) 2H2 + O2 → 2H2O
(2) 2KClO3 → 2KCl + 3O2
(3) NaOH + HCl → NaCl + H2O
(4) Fe + S → FeS
Which of the following is a general form of a decomposition reaction?
(1) AB + CD → AD + CB
(2) AB → A + B
(3) A + B → AB
(4) AB + C → AC + B
Which of the following is a photolytic decomposition reaction?
(1) 2AgBr (s) → 2Ag (s) + Br2 (g) (in sunlight)
(2) 2KClO3 → 2KCl + 3O2
(3) 2H2O → 2H2 + O2 (by electrolysis)
(4) CaCO3 → CaO + CO2
Complete the following reaction: 2H2O2 (aq) → ________ + ________
Decomposition reactions are generally ________ reactions, meaning they require energy to proceed.
Fill in the blank: The decomposition of hydrogen peroxide is catalyzed by ________ in living organisms.
The decomposition of water by passing electricity through it is called ________.
Is the following statement true or false?
All decomposition reactions require heat to occur.
Is the following statement true or false?
Decomposition reactions can be used to test for the presence of water in a sample.
State whether the following reaction is a decomposition reaction:
2H2O (l) → 2H2 (g) + O2 (g)
True or False: Electrolytic decomposition always produces gases at both electrodes.
