Solve the Problem $$\mathrm { pH } = - \log \left[ \mathrm { H } _ { 3 } \mathrm { O } ^ { + } \right]$$

Multiple Choice

Solve the problem. Round your answer to the nearest tenth, when appropriate. Use the formula $$\mathrm { pH } = - \log \left[ \mathrm { H } _ { 3 } \mathrm { O } ^ { + } \right]$$ as needed.
-Find the $\left[ \mathrm { H } _ { 3 } \mathrm { O } ^ { + } \right]$ if the $\mathrm { pH } = 2.3$ .

A) $2.7 \times 10 ^ { 1 }$
B) $3.6 \times 10 ^ { - 1 }$
C) $5.0 \times 10 ^ { - 3 }$
D) $2.0 \times 10 ^ { 2 }$