The problem can be solved using the following formula:
ΔTb = i Kb <em>m</em>
i = moles particles/moles solute
Kb = 0.512 °C/m
m = molality = moles solute/kg solvent
First we can solve for the molality of the solution:
75.0 g ZnCl₂ / 136.286 g/mol = 0.550 mol ZnCl₂
m = 0.550 mol/0.375 kg
m = 1.468 mol/kg
We can now solve for the change in temperature of the boiling point:
ΔTb = i Kb m
ΔTb = (3 mol particles/1 mol ZnCl₂) (0.512 °C/m) (1.468 m)
ΔTb = 2.25 °C
The boiling point of a solution is the initial boiling point plus the change in boiling point:
BP = 100 °C + 2.25 °C
BP = 102.25 °C
The solution will have a boiling point of 102.25 °C.
Answer:
Most solids in solution exhibit a general trend of increasing solubility with increasing temperature.
A seed crystal may be added to a supersaturated solution to precipitate excess solute.
Explanation:
For many solids dissolved in liquid water, the solubility increases with temperature. The increase in kinetic energy that comes with higher temperatures allows the solvent molecules to more effectively break apart the solute molecules that are held together by intermolecular attractions(Lumen Learning).
When a seed crystal is added to a supersaturated solution, excess solute begin to precipitate because the seed crystal now furnishes the required nucleation site where the excess dissolved crystals now begin to grow.
Oxygen has 6 valence electrons, so B
<span>The kinetic energy of its molecules has decreased</span>
