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2 years ago

Determine the number of moles in each substance.

Chemistry

1 answer:

olchik [2.2K]2 years ago

8 0

Answer:

a) 5.4 * 10^-4 moles

b) 8.2 moles

c) 0.26 moles

d) 20.76 moles

Explanation:

a)Since 1 mole of a substance has 6.02 * 10^23 atoms

x moles is present in 3.25 x 1020 atoms of lead

3.25 x 1020 atoms of lead/6.02 * 10^23 atoms = 5.4 * 10^-4 moles

b) Since 1 mole of a substance has 6.02 * 10^23 molecules

x moles is present in 4.96 x 1024 molecules of glucose

x = 4.96 x 1024 molecules of glucose/6.02 * 10^23 molecules = 8.2 moles

c) Since 1 mole of a substance has 6.02 * 10^23 formula units

x moles is present in 1.56 x 1023 formula units of sodium hydroxide

x = 1.56 x 1023 formula units /6.02 * 10^23 = 0.26 moles

d) Since 1 mole of a substance has 6.02 * 10^23 ions

x moles is present in 1.25 x 1025 copper(ll) ions

x = 1.25 x 1025 copper(ll) ions/6.02 * 10^23 ions = 20.76 moles

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3 years ago

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Answer:

See explanation

Explanation:

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