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An aqueous solution at has a h3o concentration of . Calculate the concentration. Be sure your answer has 2 significant digits.

User MrBr
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1 Answer

2 votes

Answer:

[OH⁻] = 1.1 × 10⁻³ M

Step-by-step explanation:

An aqueous solution at 25°C has a H₃O⁺ concentration of 8.8 × 10⁻¹² M. Calculate the concentration of OH⁻. Be sure your answer has 2 significant digits.

Step 1: Given data

Concentration of H₃O⁺ ([H₃O⁺]): 8.8 × 10⁻¹² M

Concentration of OH⁻ ([OH⁻]): ?

Step 2: Calculate the concentration of OH⁻

Let's consider the self-ionization of water.

2 H₂O(aq) ⇄ H₃O⁺(aq) + OH⁻(aq)

The equilibrium constant for this reaction is:

Kw = [H₃O⁺] × [OH⁻] = 1.0 × 10⁻¹⁴

[OH⁻] = 1.0 × 10⁻¹⁴ / [H₃O⁺]

[OH⁻] = 1.0 × 10⁻¹⁴ / 8.8 × 10⁻¹²

[OH⁻] = 1.1 × 10⁻³ M

User Haseeb Khan
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