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a 50.0ml solution sample of lithium hydroxide contains 3.95×10−6mol of lioh. what is the ph of the solution at 25.0∘c? round the answer to three significant figures.

User Emma Leis
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Final answer:

The pH of the lithium hydroxide solution can be calculated by finding the concentration of H3O+ ions and using the formula pH = -log[H3O+]. The pOH can be calculated by finding the concentration of OH- ions and using the formula pOH = -log[OH-]. Finally, the pH can be determined using the relationship pH + pOH = 14.

Step-by-step explanation:

The pH of a solution can be calculated using the formula: pH = -log[H3O+]. In this case, the concentration of H3O+ is given as 3.95×10−6mol in a 50.0ml solution sample of lithium hydroxide. Thus, the concentration of H3O+ can be calculated by dividing the moles of H3O+ by the volume of the solution in liters: 3.95×10−6mol/0.050L = 7.90×10−5 M.

Next, we can calculate the pOH using the relationship: pOH = -log[OH-]. Since the solution is neutral, the concentration of OH- is equal to the concentration of H3O+: 7.90×10−5 M. Therefore, the pOH can be calculated as -log(7.90×10−5) = 4.10.

Finally, we can calculate the pH using the relationship: pH + pOH = 14. Thus, pH = 14 - 4.10 = 9.90. Rounding to three significant figures gives the pH of the solution as 9.90.

User Ajay Chauhan
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