### Calculate moles from provided weight

4. Moles and Molarity 4.1) Moles 4.1.1) Moles - General

4.1.1.1) Moles - General Normal 1

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A compounder weighed 113.68 mg of sodium lactate . If the molecular weight of sodium lactate is 112 g/mol, then determine the number of milimoles present there.

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lb equals 1.015 mmol kg

The molecular weight of sodium lactate is 112 g/mol, which means (112 \quad g)/(1 \quad mol). Again, 113.68 mg equals 113.68/1000=0.11368 g of sodium lactate . Therefore, using equation method we can write:
(112 \quad g)/(1 \quad mol)=(0.11368 \quad g)/x therefore x = 0.001015 mol.
Multiplying this number with 1000 will give us milimoles;
therefore 0.001015 × 1000 = 1.015 mmol. Ans.

Using shortcut: simply divide the miligram weight (113.68 \quad mg) with molecular weight (112\quad g/(mol)). This will give us:
(113.68 \quad mg)/(112 \quad g/(mol))=1.015 \quad mmol Ans.