Question

question 33 (1 point)
use the following information to answer the next question.
the ph value egg white is 7.80.
the concentration of hydroxide ions in a sample of egg white will be
1.6 × 10⁻⁸ mol/l
6.3 × 10⁻⁷ mol/l
2.6 × 10⁻⁸ mol/l
5.8 × 10⁻⁷ mol/l
7.9 × 10⁻¹ mol/l

Explanation:

Step1: Recall pH and pOH relationship

We know that \( \text{pH} + \text{pOH} = 14 \). Given \( \text{pH} = 7.80 \), we can find \( \text{pOH} \) as \( \text{pOH}=14 - 7.80 = 6.20 \).

Step2: Recall pOH and \([\text{OH}^-]\) relationship

The formula relating \( \text{pOH} \) and hydroxide ion concentration \([\text{OH}^-]\) is \( \text{pOH}=-\log_{10}[\text{OH}^-] \), so \([\text{OH}^-]=10^{-\text{pOH}}\).
Substitute \( \text{pOH} = 6.20 \) into the formula: \([\text{OH}^-]=10^{- 6.20}\).
We can rewrite \(10^{-6.20}\) as \(10^{-6 - 0.20}=10^{-6}\times10^{-0.20}\).
Since \(10^{-0.20}\approx0.63\), then \([\text{OH}^-]=10^{-6}\times0.63 = 6.3\times 10^{-7}\space\text{mol/L}\).

Answer:

\(6.3\times 10^{-7}\space\text{mol/L}\) (the option with \(6.3\times 10^{-7}\space\text{mol/L}\))