Answer is 74,844 calories
Answer:
NaI > Na2SO4 > Co Br3
meaning that NaI has the highest freezing point, and Co Br3 has the lowest freezing point.
Explanation:
The freezing point depression is a colligative property.
That means that it depends on the number of solute particles dissolved.
The formula to calculate the freezing point depression of a solution of a non volatile solute is:
ΔTf = i * Kf * m
Where kf is a constant, m is the molality and i is the van't Hoff factor.
Molality, which is number of moles per kg of solvent, counts for the number of moles dissolved and the van't Hoff factor multipllies according for molecules that dissociate.
The higher the number of molecules that dissociate, the higher the van't Hoff, the greater the freezing point depression and the lower the freezing point.
As the question states that you assume equal concentrations (molality) and complete dissociation you just must find the number of ions generated by each solute, in this way:
NH4 I → NH4(+) + I(-) => 2 ions
Co Br3 → Co(+) + 3 Br(-) => 4 ions
Na2SO4 → 2Na(+) + SO4(2-) => 3 ions.
So, Co Br3 is the solute that generate more particles and that solution will exhibit the lowest freezing point among the options given, Na2SO4 is next and the NaI is the third. Ordering the freezing point from higher to lower the rank is NaI > Na2SO4 > CoBr3, which is the answer given.
Answer:
I and IV
Explanation:
Increasing the number of particles at one side of the reaction (H2 in this case) results in the shifting of the equilibrium to the side with lesser number of particles, so in this case the equilibrium will shift to the left (towards the reactants)
A decrease in temperature will always function to favor the exothermic reaction, and since the backwards reaction is exothermic, the equilibrium will shift to the left (towards the reactants).
Option II and V will shift the equilibrium to the products, and adding a catalyst has no effect on the equilibrium.
<h3>Hope this helps!</h3>
Explanation:
Dipole moment is defined as the measurement of the separation of two opposite electrical charges.
is a bent shaped molecule with a dipole moment of 1.87.
is also a bent shaped molecule with a dipole moment of 1.10.
is a also a bent shaped molecule and has a negligible dipole moment.
has a dipole moment of 0.29.
Therefore, given molecules are arranged according to their increasing dipole moment as follows.
< < <
Answer:
The [H+] is 2.04*10-3 and pH is 2.68
Explanation:
Barbituric acid is a a weak acid. Using Bronsted-Lowry equation, Ka = [H+][A-]/[HA]. we can calculate [H+] , we need to take barbituric acid pKa and apply antilog [-pKa] (in calculator press button 10x or ^ with negative value pKa). In that way we obtain Ka=9.77*10-5. Considering [H+]=[A-], we have than:
[H+]=√Ka*Acid Concentration=√9.77*10-5*0.043=2.04*10-3
pH=-㏒[H+]=-㏒[2.04*10-3]=2.7
I hope my answer helps you
