Q. 10.41 - An Introduction to General, Organic, and Biological Chemistry

Question

Complete the following table:

Step-by-Step Solution

Answer

i) The pH value is greater than $7.0$ and is basic

ii) The ion value $\left[O{H}^{-}\right]$ is determined as $3.09\times {10}^{-11} M$

iii) The pH value is lesser than $7$ and is acidic

Step 1 : Introduction

The given is the table with components

The objective is to complete the table

Step 2 : Explanation

(i)

$$\begin{gathered} [OH-]=1.0 \times {10}^{-6}M \\ \left[H_3{O}^{+}\right]= \\ \left[H_3{O}^{+}\right]= \\ \left[H_3{O}^{+}\right]=1.0 \times {10}^{-8}M \\ pH=-\log \left[H_3{O}^{+}\right] \\ pH=-\log [1.0 \times {10}^{-8}]=8 \\ pH>7.0 \\ so, basic \end{gathered}$$

Step 3 : Explanation

(ii)

$$\begin{gathered} pH=3.49<7.0 \\ so, Acidic \\ \left[H_3{O}^{+}\right]={10}^{-pH} \\ \left[H_3{O}^{+}\right]={10}^{-3.49}=3.236 \times {10}^{-4}M \\ \left[O{H}^{-}\right]= \\ \left[O{H}^{-}\right]==3.09 \times {10}^{-11} M \end{gathered}$$

Step 4 : Explanation

(iii)

$$\begin{gathered} \left[H_3{O}^{+}\right]=2.8 \times {10}^{-5}M \\ \left[O{H}^{-}\right]= \\ \left[O{H}^{-}\right]= \\ [OH-]=3.571 \times {10}^{-10}M \\ pH=-\log \left[H_3{O}^{+}\right] \\ pH=-\log [2.8 \times {10}^{-5}]=4.55 \\ pH<7.0 \\ so, Acidic \end{gathered}$$