To convert moles to kg, you need to multiply the number of moles by the molar mass (g/mol) of the substance and then divide by 1000 to convert grams to kilograms.
Here's a breakdown:
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Find the Molar Mass: Determine the molar mass of the substance. The molar mass is the mass of one mole of a substance and is usually expressed in grams per mole (g/mol). You can find this information on the periodic table (for elements) or by adding the atomic masses of all atoms in a compound's formula.
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Calculate Mass in Grams: Multiply the number of moles by the molar mass. This will give you the mass of the substance in grams.
Mass (grams) = Moles × Molar Mass (g/mol)
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Convert Grams to Kilograms: Divide the mass in grams by 1000 to convert it to kilograms.
Mass (kg) = Mass (grams) / 1000
Formula:
Mass (kg) = (Moles × Molar Mass (g/mol)) / 1000
Example:
Let's say you have 2 moles of water (H₂O) and you want to find its mass in kg.
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Molar Mass of Water: The molar mass of H₂O is approximately 18.015 g/mol (1.008 g/mol for each H and 15.999 g/mol for O).
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Calculate Mass in Grams: 2 moles × 18.015 g/mol = 36.03 grams
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Convert Grams to Kilograms: 36.03 grams / 1000 = 0.03603 kg
Therefore, 2 moles of water is approximately 0.03603 kg.
In Summary: Convert moles to kg by multiplying the number of moles by the molar mass (in g/mol) of the substance and then dividing the result by 1000.
