Answer : The mass of sodium bromide added should be, 18.3 grams.
Explanation :
Molality : It is defined as the number of moles of solute present in kilograms of solvent.
Formula used :

Solute is, NaBr and solvent is, water.
Given:
Molality of NaBr = 0.565 mol/kg
Molar mass of NaBr = 103 g/mole
Mass of water = 315 g
Now put all the given values in the above formula, we get:


Thus, the mass of sodium bromide added should be, 18.3 grams.
When you immerse an ionic compound<span> in </span>water<span>, the ions are attracted to the </span>water <span>molecules, each of which carries a polar charge. If the attraction between the ions and the </span>water <span>molecules </span>is<span> great enough to break the bonds holding the ions together, the compound </span>dissolves<span>. </span>
The concentration of a solution can be expressed in (4) <span>moles per liter~</span>
The answer is dissolved in water, because in chemistry, (aq) is shorthand for aqueous solution.