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3 years ago

How many moles of KOH are there in 27.5 mL of 0.250 M KOH?

Chemistry

1 answer:

zaharov [31]3 years ago

7 0

Answer:

6.88 × 10^-3mol

Explanation:

Molarity = number of moles (n) ÷ volume (V)

According to this question, there in 27.5 mL of 0.250 M KOH, the number of moles of KOH can, therefore, be calculated as follows:

number of moles = molarity × volume

Volume of KOH = 27.5mL = 27.5/1000

= 0.0275L

n = 0.0275 × 0.250

n = 0.006875 mol

n = 6.88 × 10^-3mol

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3 years ago

A chemist must prepare of potassium hydroxide solution with a pH of at . He will do this in three steps: Fill a volumetric flask

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The question is incomplete; the complete question is:

A chemist must prepare 800.0mL of potassium hydroxide solution with a pH of 13.00 at 25 degree C. He will do this in three steps: Fill a 800.0mL volumetric flask about halfway with distilled water. Weigh out a small amount of solid potassium hydroxide and add it to the flask. Fill the flask to the mark with distilled water. Calculate the mass of potassium hydroxide that the chemist must weigh out in the second step. Round your answer to 2 significant digits.

Answer:

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Explanation:

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