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What are [H3O+], [OH?], and pH in a solution with a pOH of 11.17? Make sure your answers are given to the correct number of significant figures.

[H3O+] = __ x 10 __ M
[OH?] = __ x 10 __ M
pH= __

User Khoamle
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1 Answer

5 votes

Answer:

[OH⁻]= 6.76*10⁻¹² M

pH= 2.83

[H₃O⁺]= 1.48*10⁻³

Step-by-step explanation:

The pOH (or potential OH) is a measure of the basicity or alkalinity of a solution that indicates the concentration of hydroxyl ions [OH-] present in a solution. The pOH is defined as the logarithm of the concentration of OH- ions, with the sign changed:

pOH= -log[OH⁻]

In this case, pOH= 11.17. So:

11.17= -log [OH⁻]

Solving:

-11.17=log [OH⁻]

10⁻¹¹ ¹⁷= [OH⁻]

6.76*10⁻¹² M= [OH⁻]

pH, short for hydrogen potential, is a parameter that indicates the concentration of hydrogen ions [H⁺] or [H₃O⁺] that exist in a solution and is calculated as the logarithm of the concentration of H⁺ ions, with the sign changed:

pH= -log[H⁺]= -log[H₃O⁺]

The relationship between pH and pOH can be established by the expression:

pH + pOH= 14

In this case, being pOH=11.17:

pH + 11.17= 14

and solving you get:

pH= 14 - 11.17

pH= 2.83

Finally, replacing this value in the definition of pH:

2.83= -log [H₃O⁺]

and solving you get:

-2.83= log [H₃O⁺]

10⁻² ⁸³= [H₃O⁺]

1.48*10⁻³= [H₃O⁺]

User Pierce McGeough
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