How many grams of NaCl would need to be added to 1001 g of water to increase the boiling temperature of the solution by 1.500 °C? (Kb for water is 0.5100 °C/m)

Answer : The mass of NaCl needed would be, 86.1 grams.

Explanation :

Formula used for Elevation in boiling point :

or,

where,

= change in temperature =

= boiling point constant  =

m = molality

i = Van't Hoff factor = 2 (for NaCl electrolyte)

= mass of solute (NaCl) = ?

= mass of solvent (water) = 1001 g

= molar mass of solute (NaCl) = 58.5 g/mol

Now put all the given values in the above formula, we get:

Therefore, the mass of NaCl needed would be, 86.1 grams.

a. energy is absorbed in the reaction.

if in a given reaction the energy of products is greater than the energy of reactants it means that reaction is endothermic and during the reaction, the energy is absorbed by reactants. in an endothermic reaction, the products have more stored chemical energy than the reactants. and in this reaction the reactants are more stable than products before the compounds with less energy are always more stable.