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Question
What is the difference between molality and molarity?
Solution
The number of moles of a substance (known as the solute) dissolved in precisely 1 litre of a solution is known as molarity (solvent and solute combined). As a result, the formula for estimating molarity is as follows:
Molarity = `"Number of moles of solute"/"Volume in litre"`
The term molarity is also used to refer to molar concentration. As a result, molar concentration measurement is based on the volume of liquid in which a substance is dissolved. It's vital to remember that the volume is in litres, so if we have volume in mL we need to convert that in litres,
Molality is the number of moles of substance (also known as the solute) found in a given mass of solvent (in Kg) in which it is dissolved
Molality is calculated by using the formula.
Major differences between Molarity and Molality ar given as follows:
1) Molarity is the concentration of a material determined as the number of moles of solute dissolved in poe litre of solution, whereas morality is the concentration calculated as the number of moles of solute found in one kilogram of solvent.
2) Molality is denoted by the symbol m, whereas molarity is denoted by the symbol M.
3) The molarity formula is moles per litre, but the morality is formula is moles per kilogram.
4) Molarity is impacted by temperature changes, whereas morality is affected by temperature changes.
5) changes in pressure affect molarity, but they do not affect molality.
6) Molarity can lead to an imprecise and inaccurate concentration, whereas molarity can lead to an accurate and precise concentration measurement.
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