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Calculate the concentration of [OH-] in a solution in which:

a. [H₃O⁺] = 2.0 x 10⁻⁶
b. [H₃O⁺] = 100 x [OH⁻]
c. [H₃O⁺] = [OH⁻]

User Anthony N
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1 Answer

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Final answer:

To calculate the concentration of [OH-] in a solution, you can use the formula [OH-] = 10^-14 / [H3O+].

To determine the concentration of hydroxide ions ([OH-]), one can use the relationship that the product of [H3O+] and [OH-] in water at 25 °C is a constant 1.0×10⁻¹⁴. Calculations are made for specific values of [H3O+], and [OH-] is found accordingly for each given scenario.

Step-by-step explanation:

In order to calculate the concentration of [OH-] in a solution using the given [H3O+] concentration, you can use the formula:

[OH-] = 10-14 / [H3O+]

For example, if [H3O+] = 2.0 x 10-6 M, then:

[OH-] = 10-14 / (2.0 x 10-6)

Simplifying the calculation, you get [OH-] = 5 x 10-9 M.

Therefore, the concentration of [OH-] in the solution is 5 x 10-9 M.

To determine the concentration of hydroxide ions ([OH-]), one can use the relationship that the product of [H3O+] and [OH-] in water at 25 °C is a constant 1.0×10⁻¹⁴. Calculations are made for specific values of [H3O+], and [OH-] is found accordingly for each given scenario.

To calculate the concentration of hydroxide ions ([OH-]) in a solution, we can use the following information:

The product of the hydronium ion concentration ([H3O+]) and the hydroxide ion concentration ([OH-]) in an aqueous solution at 25 °C is always 1.0×10⁻¹⁴.

For the given values of [H3O+], we can calculate [OH-] using the formula [H3O+] × [OH-] = 1.0×10⁻¹⁴.

Calculations:

  1. [OH-] when [H3O+] = 2.0 x 10⁻⁶
    [OH-] = 1.0×10⁻¹⁴ / [H3O+]
    [OH-] = 1.0×10⁻¹⁴ / (2.0 x 10⁻⁶)
    [OH-] = 5.0 x 10⁻⁹ M
  2. When [H3O+] = 100 x [OH-], rearranging and solving gives us:
    [OH-] = 1.0×10⁻¹⁴ / (100 x [OH-])
    After solving we get:
    [OH-] = 1.0 x 10⁻⁷ M
  3. If [H3O+] = [OH-], then:
    [OH-] = [H3O+] = √(1.0 x 10⁻¹⁴) = 1.0 x 10⁻⁷ M

User Mmln
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