Question

ph = 2.52
express your answer using two significant figures.
oh⁻ = m

Explanation:

Step1: Find pOH from pH

We know that \( \text{pH} + \text{pOH} = 14 \). Given \( \text{pH} = 2.52 \), so \( \text{pOH}=14 - 2.52 = 11.48 \).

Step2: Calculate \([\text{OH}^-]\) from pOH

The formula relating pOH and \([\text{OH}^-]\) is \( \text{pOH}=-\log_{10}[\text{OH}^-] \), so \( [\text{OH}^-]=10^{-\text{pOH}} \). Substituting \( \text{pOH} = 11.48 \), we get \( [\text{OH}^-]=10^{- 11.48} \). Calculate \( 10^{-11.48}\approx3.311\times 10^{-12} \).

Step3: Round to two significant figures

Rounding \( 3.311\times 10^{-12} \) to two significant figures gives \( 3.3\times 10^{-12} \).

Answer:

\( 3.3\times 10^{-12} \)