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3 years ago

How many moles of potassium are in 3.78 x 10^21 atoms of K?

Chemistry

1 answer:

lbvjy [14]3 years ago

3 0

Answer: 6.3 x 10^-3 moles

Explanation:

Based on Avogadro's law:

1 mole of any substance has 6.02 x 10^23 atoms

So, 1 mole of potassium = 6.02 x 10^23 atoms

Z moles = 3.78 x 10^21 atoms

To get the value of Z, we cross multiply:

(3.78 x 10^21 atoms x 1mole) = (6.02 x 10^23 atoms x Z moles)

3.78 x 10^21 = (6.02 x 10^23 x Z)

Z = (3.78 x 10^21) ➗ (6.02 x 10^23)

Z = 0.63 x 10^-2)

Place the result in standard form

Hence, Z = 6.3 x 10^-3 moles

Thus, there are 6.3 x 10^-3 moles of potassium in 3.78 x 10^21 atoms of K.

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Bess [88]

Answer:

pH = 1.95

Explanation:

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3 years ago

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IceJOKER [234]

Answer:

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Explanation:

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The mole ratio of Silver nitrate to nitric acid based on the balanced equation is 3AgNO3:4HNO3.

Using this we can create a table: The table is attached.

Breakdown of the table.

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