Answer
a. Acidic
b. Acidic
c. Basic
d. Acidic
Work Step by Step
a. The concentration of $H_{3}O$+ is more than $10^{-7}$ hence the solution is acidic
b. The concentration of $H_{3}O$+ is more than $10^{-7}$ hence the solution is acidic
c. The concentration of OH- is more than $10^{-7}$ hence solution is basic.
d. The concentration of $H_{3}O$+ is more than $10^{-7}$ hence the solution is acidic