Molality is defined as the number of moles of solute per 1000 grams of solvent and is denoted by m. Molality can be more precise than molarity, since both solute and solvent are weighed. (A 1.00 millimolal solution contains 1.00 millimole of solute dissolved in 1000 grams of solvent). However, molality is not widely used in laboratories. (N.B. It is important not to confuse molality with molarity).