Answer: CoBr3 < K2SO4 < NH4 Cl
Justification:
1) The depression of the freezing point of a solution is a colligative property, which means that it depends on the number of particles of solute dissolved.
2) The formula for the depression of freezing point is:
ΔTf = i * Kf * m
Where i is the van't Hoof factor which accounts for the dissociation of the solute.
Kf is the freezing molal constant and only depends on the solvent
m is the molality (molal concentration).
3) Since, you are assuming equal concentrations and complete dissociation of the given solutes, the solute with more ions in the molecular formula will result in the solution with higher depression of the freezing point (lower freezing point).
4) These are the dissociations of the given solutes:
a) NH4 Cl (s) --> NH4(+)(aq) + Cl(-) (aq) => 1 mol --> 2 moles
b) Co Br3 (s) --> Co(3+) (aq) + 3Br(-)(aq) => 1 mol --> 4 moles
c) K2SO4 (s) --> 2K(+) (aq) + SO4 (2-) (aq) => 1 mol --> 3 moles
5) So, the rank of solutions by their freezing points is:
CoBr3 < K2SO4 < NH4 Cl
The Change in Gibb's free energy, ΔG for the reaction at 298K is; -56.92KJ.
<h3>Gibb's free energy of reactions</h3>
It follows from the Gibb's free energy formula as expressed in terms of Enthalpy and Entropy that;
On this note, it follows that;
Hence, the Gibb's free energy for the reaction is;
- ΔG = 14.6 - 71.52
- ΔG = -56.92KJ
Remarks: The question requires that we determine the Gibb's free energy for the reaction at 298K.
Read more on Gibb's free energy;
brainly.com/question/13765848
Conduction - by touch
Convection - hot air rises, cold air sinks
Insulation - to insulate or capture heat
Radiation - by waves
Direct contact means touch, therefore the answer would be conduction.
Answer:Molarity
Explanation:M stand for molarity
