When pentane C5H12 is burned in excess oxygen, the products of the reaction are CO2(g) and H2O(l). In the balanced equation for this combustion,C5H12(g) _ O2 (g) → 5CO2(g) + 6H2O(l) the coefficient of the oxygen should be:
Correct answer: D. 8
- A. 16
- B. 12
- C. 11
- D. 8
Explanation
When hydrocarbon reacts with oxygen it forms carbon dioxide and water.C5 H1 2+O2 →CO2 +H2 OStart by using the 5 carbons in the hydrocarbon to form 5 carbon dioxide.Then use the 12 hydrogens to form 6 waters. Then count up the oxygen atoms needed.5×O2 =10O6×O1 =6O = 16There must be 16 oxygens on the left or reactants to balance the equation. So8×O2 =16OHence,1×C5 H12 +8×O2 →5×CO2 +6H2 OThe balanced equation is:C5 H12 +8O2 →5CO2 +6H2 O
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