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3 years ago

Determine the pH of a KOH solution made by mixing 0.251 g KOH with enough water to make 1.0 × 10 2 mL of solution

Chemistry

1 answer:

vesna_86 [32]3 years ago

6 0

Answer:

pH = 12.65

Explanation:

From the given information:

number of moles =mass in gram / molar mass

number of moles of KOH = mass of KOH / molar mass of KOH

number of moles of KOH = 0.251 g / 56.1 g/mol = 0.004474 mol

For solution :

number of moles = Concentration × volume

concetration = number of moles/ volume

concetration = 0.004474 mol / 0.100 L

concetration = 0.04474 M

We know that 1 moles KOH result into 1 mole OH⁻ ions

Therefore, Molarity of OH⁻ = 0.04474 M

Now,

pOH = -log[OH⁻]

pOH = -log (0.04474) M

pOH = 1.35

Similarly,

pH + pOH = 14

pH = 14 - pOH

pH = 14 - 1.35

pH = 12.65

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3 years ago

An aqueous sodium acetate, NaC2H3O2 , solution is made by dissolving 0.395 mol NaC2H3O2 in 0.505 kg of water. Calculate the mola

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2 years ago

If you were to react 4.3 miles of magnesium phosphide how many moles of potassium would you need?

bixtya [17]

Answer:

25.8

Explanation:

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And now let's balance this equation:

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We see that the ratio of magnesium-phosphide and potassium is 1:6, which means that for every mole of magnesium-phosphide there need to be 6 moles of potassium.

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2 years ago

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3 years ago

Read 2 more answers

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lord [1]

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