Chapter 16, Problem 54A

Interpretation Introduction

Interpretation:

The condition of a solution to be basic is to be chosen.

Concept introduction:

According to Arrhenius,

Acid is a substance which gives hydrogen ion and Base is a substance which gives hydroxyl ions in aqueous solution.

  $If\left[H^{+}\right]=\left[O{H}^{-}\right]$or $pH=pOH$, the solution is neutral.

  $If\left[H^{+}\right]<\left[O{H}^{-}\right]$ or $pH>7$ , the solution is basic.

  $If\left[H^{+}\right]>\left[O{H}^{-}\right]$ or $pH<7$, the solution is acidic.

Answer to Problem 54A

Correct Answer: Option (a), (c) and (d).

Explanation of Solution

Reason for correct option:

(a)

  $pOH<7$

As $pH+pOH=14$

Therefore, $pOH=14-pH$

Or $\begin{array}{l}14-pH<7\\ pH>7\end{array}$

It means solution is basic.

(b) Given data:

  $pH>7$

It means solution is basic.

(d)$\left[H^{+}\right]<1\times {10}^{-7}M$

Because

  $pH=-\log \left[H^{+}\right]$

Therefore, $pH>7$

It means solution is basic.

Conclusion

Reason for incorrect option:

(c)

  $\left[O{H}^{-}\right]<\left[H^{+}\right]$

It means solution is acidic.