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Question
Define Molarity (M).
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Solution 1
Molarity (M) is defined as the number of moles of the solute dissolved in one Litre (or one cubic decimetre) of solution.
It is expressed as:
Molarity (M) = `"Moles of solute"/"Volume of Solution in Litre"`
For example, a 0.25 mol L−1 (or 0.25 M) solution of NaOH means that 0.25 mol of NaOH has been dissolved in one litre (or one cubic decimetre).
Solution 2
It is defined as the number of moles of solute present in 1000 mL of the solution. Molarity is represented by M.
Molarity (M) = `"Number of moles of solute"/"Volume of solution in mL" xx 1000`
or
M = `"Weight of solute"/"Molar mass of solute × Volume of solution in mL" xx 1000`
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