Question

Molarity is defined as:
A. the number of moles of solute dissolved in $1d{m^3}$ of the solution.
B. the number of moles of solute dissolved in $1kg$ of solvent.
C. the number of moles of solute dissolved in $1d{m^3}$ of the solvent.
D. the number of moles of solute dissolved in $100ml$ of the solvent.

Answer 1

Molarity basically expresses the concentration of a solution. Molarity is also known as molar concentration. Firstly, Students need to understand the concept of concentration, also about the solute and solvent, then they can easily answer this question.

Complete answer: The units of molarity are moles per cubic decimetre, denoted as mol dm-3 or basically M. The cubic decimetre is similar to litre. Students will find that the molarity was previously denoted by moles per litre, composed mol l-1.In mathematical from, molarity can be defined as:
$M = \dfrac{n}{V}$
Where M = Molality of the concentration
n = Number of moles of the solute
V = Volume of concentration in litres
Molarity is a unit of concentration estimating the quantity of moles of a solute for each litre of solution.

Additional Information: 1 litre = 1dm3 .Basically, to calculate molarity ,2 values are necessary for the students. Firstly, number of moles of solute and secondly, the concentration of the solution.

Hence the correct option is (A).

Note: Students should be mindful so as not to confuse molality and molarity. Molality's units are denoted to by a lowercase "m" though molarity are denoted to by a capitalized "M". Also, students should practice numerical based on molarity and molality as they are really useful for both the boards as well as for the competitive exams.