Ph Poh H Oh- Calculator For Chemistry

pH and pOH Equations:

\[ pH = -\log_{10}[H^+] \] \[ pOH = -\log_{10}[OH^-] \] \[ [H^+] = 10^{-pH} \] \[ [OH^-] = 10^{-pOH} \] \[ pH + pOH = 14 \] \[ [H^+][OH^-] = 10^{-14} \]

[H+] Concentration:

mol/L

[OH-] Concentration:

mol/L

pH Value:

unitless

pOH Value:

unitless

Calculated Results:

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1. What Are pH and pOH?

pH and pOH are measures of acidity and alkalinity of aqueous solutions. pH represents the negative logarithm of hydrogen ion concentration, while pOH represents the negative logarithm of hydroxide ion concentration. They are related by the equation: pH + pOH = 14 at 25°C.

2. How Does the Calculator Work?

The calculator uses the fundamental equations of acid-base chemistry:

\[ pH = -\log_{10}[H^+] \] \[ pOH = -\log_{10}[OH^-] \] \[ [H^+] = 10^{-pH} \] \[ [OH^-] = 10^{-pOH} \] \[ pH + pOH = 14 \] \[ [H^+][OH^-] = 1 \times 10^{-14} \]

Where:

\( [H^+] \) — Hydrogen ion concentration (mol/L)
\( [OH^-] \) — Hydroxide ion concentration (mol/L)
\( pH \) — Measure of acidity (0-14 scale)
\( pOH \) — Measure of alkalinity (0-14 scale)
\( 10^{-14} \) — Ion product of water (Kw) at 25°C

3. Importance of pH Calculation

Details: pH calculations are essential in chemistry, biology, environmental science, and many industrial processes. They help determine solution acidity/alkalinity, predict chemical behavior, and maintain optimal conditions for biological systems.

4. Using the Calculator

Tips: Enter any one known value (H+ concentration, OH- concentration, pH, or pOH) and the calculator will compute the other three values. Values must be within valid ranges (pH/pOH: 0-14, concentrations: positive numbers).

5. Frequently Asked Questions (FAQ)

Q1: What is the relationship between pH and pOH?
A: pH and pOH are inversely related and always sum to 14 in aqueous solutions at 25°C (pH + pOH = 14).

Q2: What does a pH of 7 indicate?
A: A pH of 7 indicates a neutral solution where [H+] = [OH-] = 10⁻⁷ M.

Q3: How does temperature affect pH calculations?
A: The ion product of water (Kw) changes with temperature, so the relationship pH + pOH = 14 is only exact at 25°C.

Q4: What are typical pH values for common substances?
A: Battery acid: ~1, Lemon juice: ~2, Vinegar: ~3, Pure water: 7, Baking soda: ~9, Ammonia: ~11, Bleach: ~13.

Q5: Why are logarithmic scales used for pH?
A: Logarithmic scales compress the wide range of hydrogen ion concentrations (10⁰ to 10⁻¹⁴ M) into a manageable 0-14 scale.