<u>Answer:</u> The freezing point of solution is -0.454°C
<u>Explanation:</u>
Depression in freezing point is defined as the difference in the freezing point of pure solution and freezing point of solution.
The equation used to calculate depression in freezing point follows:

To calculate the depression in freezing point, we use the equation:

Or,

where,
Freezing point of pure solution = 0°C
i = Vant hoff factor = 2
= molal freezing point elevation constant = 1.86°C/m
= Given mass of solute (KCl) = 5.0 g
= Molar mass of solute (KCl) = 74.55 g/mol
= Mass of solvent (water) = 550.0 g
Putting values in above equation, we get:

Hence, the freezing point of solution is -0.454°C
Answer:
The pressure increases.
Explanation:
According to Avogadro's principle, equal volume of gases contains the same number of moles. From the reaction equation, there is a decrease in the total number of moles from reactant to product indicating a decrease in volume (as per Avogadro) and an increase in pressure according to Boyle's Law-Volume is inversely proportional to pressure.
Answer:
The nucleus (center) of the atom contains the protons (positively charged) and the neutrons (no charge). The outermost regions of the atom are called electron shells and contain the electrons (negatively charged).