Moles to grams and grams to moles

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What is a mole in chemistry?

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A mole is a unit of measurement used to express the amount of a substance. It is defined as the amount of substance that contains as many entities (atoms, molecules, etc.) as there are in 12 grams of carbon-12.

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How do you convert grams to moles?

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To convert grams to moles, divide the mass of the substance (in grams) by its molar mass (in grams per mole). Formula: Moles = Mass (g) / Molar Mass (g/mol).

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How do you convert moles to grams?

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To convert moles to grams, multiply the number of moles by the molar mass of the substance. Formula: Mass (g) = Moles x Molar Mass (g/mol).

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What is the molar mass of potassium sulfide (K2S)?

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The molar mass of potassium sulfide (K2S) is approximately 110.26 g/mol.

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Calculate the number of moles in 25.0 grams of potassium sulfide (K2S).

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0.23 moles.

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What is the molar mass of calcium (Ca)?

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The molar mass of calcium (Ca) is approximately 40.08 g/mol.

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Calculate the number of moles in 25.0 grams of calcium (Ca).

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0.62 moles.

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What is the molar mass of zinc sulfide (ZnS)?

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The molar mass of zinc sulfide (ZnS) is approximately 97.44 g/mol.

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Calculate the number of moles in 15.0 grams of zinc sulfide (ZnS).

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0.15 moles.

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What is the percent composition of an element in a compound?

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Percent composition is the percentage by mass of each element in a compound. It is calculated by dividing the mass of the element in one mole of the compound by the molar mass of the compound, then multiplying by 100.