Ph To Oh Concentration Calculator Formula

pH to OH^- Formula:

\[ [OH^-] = 10^{-(14 - pH)} \]

Hydroxide Ion Concentration [OH^-]:

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1. What is the pH to OH^- Formula?

The formula calculates the concentration of hydroxide ions ([OH^-]) in a solution from its pH value. It's derived from the water ion product constant (K_w = 1×10^-14 at 25°C).

2. How Does the Calculator Work?

The calculator uses the formula:

\[ [OH^-] = 10^{-(14 - pH)} \]

Where:

\( [OH^-] \) — Hydroxide ion concentration (mol/L)
\( pH \) — pH value of the solution (0-14 scale)
14 — Negative logarithm of water ion product (pK_w)

Explanation: The formula converts pH to pOH (14 - pH) and then calculates the antilogarithm to get the hydroxide ion concentration.

3. Importance of OH^- Concentration

Details: Knowing hydroxide ion concentration is essential for understanding solution alkalinity, chemical reaction rates, and biological systems where pH balance is crucial.

4. Using the Calculator

Tips: Enter a pH value between 0 and 14. The calculator will display the hydroxide ion concentration in both decimal and scientific notation.

5. Frequently Asked Questions (FAQ)

Q1: What is the relationship between pH and OH^- concentration?
A: They have an inverse logarithmic relationship. As pH increases (more basic), OH^- concentration increases exponentially.

Q2: What are typical OH^- concentrations?
A: In neutral water (pH 7), [OH^-] = 1×10^-7 mol/L. At pH 10, [OH^-] = 1×10^-4 mol/L.

Q3: Does temperature affect this calculation?
A: Yes, the pK_w value changes with temperature. This calculator uses the standard 25°C value of 14.

Q4: Can I calculate pOH from this?
A: Yes, pOH is simply 14 - pH. The OH^- concentration is then 10^-pOH.

Q5: How precise are these calculations?
A: Very precise for dilute aqueous solutions at 25°C. For highly concentrated solutions or different temperatures, more complex calculations are needed.