Is water's molar mass 17 or 18 g/mol?
The subscript 2 in H2O is easy to miss in a molar mass. Count it once, and every conversion after stays right.
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3 lessons for “Molarity”
0.50 mol in 2.0 L: 0.25 M or 4 M?
Half a mole of salt in two liters of solution. Is the answer 0.25 M or 4 M? The definition settles it.
Try this lesson36 g of water: 2 moles or half a mole?
36.0 g of water is 2.00 mol, and 2.00 mol of CO2 is 88.0 g. Practice reading the units to choose divide or multiply.
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