Answer:
Molar mass of unknown solute is 679 g/mol
Explanation:
Let us assume that the solute is a non-electrolyte.
For a solution with non-electrolyte solute remains dissolved in it -
Depression in freezing point of solution, 
where, m is molality of solute in solution and 
is cryogenoscopic constant of solvent.
Here 
If molar mass of unknown solute is M g/mol then-
So, 
so, M = 679 g/mol
An exothermic process is one that gives off heat.
Explanation:
This heat is transferred to the surroundings. An endothermic process is one in which heat has to be supplied to the system from the surroundings.
Answer:
2cm^3
Explanation:
Use the density triangle: D=MxV
Switch for variables, V=M/D
Plug in numbers, 15.8g/7.9g/cm^3=2cm^3
Answer:
The solution is 50 %wt
Explanation:
50% wt is a sort of concentration and means, that 50 g of solute (in this case, the potassium bromide) dissolved in 100 g of water.
It is the same to say, that there are 50g of KBr for every 100g of H₂O
