All of the questions here are pertaining to the colligative properties of a solution and the preparation of solutions. Maybe, it would be best if you understand the equations to be used in order to answer these questions.<span>
Freezing point depression or Boiling point elevation:
</span><span>ΔT = -K (m) (i)
</span>ΔT is the change in the freezing point or the boiling point not the freezing point/boiling point. Therefore, it should be added to the original value of the property of the solvent.
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K is a constant called the molal freezing point depression constant and for the boiling point is the boiling point elevation constant. It is a property of the solvent.
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m is the concentration of the solute in the solvent in terms of molality or kg solute/kg solvent.
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i is the vant hoff factor which will represent the number of ions which the solute dissociates when in solution.</span>
Answer:

Explanation:
Balanced equation: CO(g) + H₂O(g) ⟶ CO₂(g) + H₂(g)
We can calculate the enthalpy change of a reaction by using the enthalpies of formation of reactants and products

(a) Enthalpies of formation of reactants and products

(b) Total enthalpies of reactants and products

(c) Enthalpy of reaction
This is the reaction formula,
4Fe+3O2=2Fe2O3
<span>3Fe+202=Fe3O4
it has o</span>xygen atom after it's rusted
Answer:
= -356KJ
<em>therefore, the reaction where heat is released is exothermic reaction since theΔH is negative</em>
Explanation:
given that enthalpy of gaseous reactants decreases by 162KJ and workdone is -194KJ
then,
change in enthalpy (ΔH) = -162( released energy)
work(w) = -194KJ
change in enthalpy is said to be negative if the heat is evolved during the reaction while heat change(ΔH) is said to be positive if the heat required for the reaction occurs.
At constant pressure the change in enthalpy is given as
ΔH = ΔU + PΔV
ΔU = change in energy
ΔV = change in volume
P = pressure
w = -pΔV
therefore,
ΔH = ΔU -W
to evaluate energy change we have,
ΔU =ΔH + W
ΔU = -162+ (-194KJ)
= -356KJ
<em>therefore, the reaction where heat is released is exothermic reaction since theΔH is negative</em>