SAT II Chemistry : Balancing Equations

Study concepts, example questions & explanations for SAT II Chemistry

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Example Questions

Example Question #1 : Balancing Equations

When the equation for the reaction shown below is balanced with the lowest whole-number coefficients, what is the sum of the coefficients of the reactants?

___ \(\displaystyle C_{4}H_{10} +\) ___\(\displaystyle O_{2}\) \(\displaystyle \rightarrow\) ___ \(\displaystyle H_{2}O +\) ___\(\displaystyle CO_{2}\)

Possible Answers:

\(\displaystyle 8\)

\(\displaystyle 33\)

\(\displaystyle 15\)

\(\displaystyle 7.5\)

\(\displaystyle 17\)

Correct answer:

\(\displaystyle 15\)

Explanation:

The coefficients of the equation, when balanced, should be 2, 13, 10, and 8. This problem wants to know the sum of the reactants, so only the coefficients on the left side of the reactants should be added. The sum of 2 and 13 is 15, so 15 is the correct answer.

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