A student investigated the combustion of propane (C3H8) in a school laboratory. The gas was burned in excess oxygen.

Which equation correctly represents the complete combustion of propane?

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Question

A student investigated the combustion of propane (C3H8) in a school laboratory. The gas was burned in excess oxygen.

Which equation correctly represents the complete combustion of propane?

Accepted Answer

C3H8 + 5O2 → 3CO2 + 4H2O — Award 1 mark for the correctly balanced equation. A is incorrect — CO is formed in incomplete combustion, not complete combustion. C is incorrect — the equation is not balanced; 4O2 provides only 8 oxygen atoms but 10 are needed. D is incorrect — the equation is not balanced for hydrogen; 8 hydrogen atoms require 4H2O not 3H2O.

Answer

C3H8 + 5O2 → 3CO2 + 4H2O

Answer

C3H8 + 5O2 → 3CO2 + 3H2O

Answer

C3H8 + 4O2 → 3CO2 + 4H2O

Answer

C3H8 + 3O2 → 3CO + 4H2O

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