Question

Is 1m concentrated?

Answer 1

The letter m of 1m refers to molality. The term molality is used while we deal with solutions. The term molality is used and calculated to define anything which is related to the concentration of that solution and is represented in terms of moles/Kg.

Complete step-by-step answer: Before going into the solution for the question, we should have some basic idea on solution state, the components present in them and how to express the concentration terms.
First we can discuss what the solution refers to. Solution is defined as a homogeneous mixture of two or more compounds. The term homogeneous mixture refers to the state in which every component will be present in the same amount throughout the solution i.e. the composition of the solution will be in a regular pattern.
In a solution there are two main components which are solute and a solvent. The solute is the component which is getting dissolved in a medium i.e. it is the dispersed phase and the solvent is the component which dissolves the dispersed medium and is called a dispersion medium. The solute and solvent can be of any three phases i.e. solid, liquid and gas. According to the combination between each phase of solute-solvent pair they are classified into many types.
Now to define the concentration of the solution, i.e. the amount of solute present in a solution, or the amount of solvent required to dissolve the given amount of solute, we use different concentration terms like molarity, molality, mole fraction, normality etc.
Now we have to discuss a 1 molal solution. Molality is the measure of the number of moles of solute present in 1000g or 1Kg of the solvent.
And the expression for molality is as follows:
$Molality=\frac{No.\,of\,moles\,of\,solute}{Mass\,of\,solvent\,in\,Kg}$ or,
$Molality=\frac{No.\,of\,moles\,of\,solute}{Mass\,of\,solvent\,in\,g}\times 1000$
1 molal concentration refers to 1 mole of solute present in every 1Kg of solvent, and the 1molal solution can be considered as concentrated but it is less concentrated than the 1 molar (1M) solution.

Note: 1M solution is more concentrated than 1m solution since in 1M solution, 1 mole of solution is present in solvent of mass less than 1000 grams whereas in 1molal solution 1 mole of solute present in 1000grams of solvent.
Caution should be given while solving problems related to molality, since many make the mistake of writing the mass of solution in terms of Kg as the denominator in the equation instead of mass of solvent.