A Solution Is an Acid If Its PH Is Less $10 ^ { - 9.7 }$

A solution is an acid if its pH is less than 7 and a base if its pH is greater than 7. The pH is defined by pH = -log10[H+],
where [H+] is the concentration of hydrogen ions in the solution. Use this information to answer the question
-The concentration of hydrogen ions in a solution is approximately $10 ^ { - 9.7 }$ . What is the pH of the solution? Is the solution an acid or a base?

A) The $\mathrm { pH }$ is 9.7. The solution is a base.
B) The $\mathrm { pH }$ is 9.7. The solution is an acid.
C) The $\mathrm { pH }$ is $- 9.7$ . The solution is a base.
D) The $\mathrm { pH }$ is $- 9.7$ . The solution is an acid.