Answer: the second option: <span>Iron is being oxidized
</span>
Explanation:
1) Oxidation is the increase of the oxidation state (number) due to the loss of electrons.
2) In the given reaction, you can see that in the left side the atom is Fe.
When an element (atom) is not combined (or combined with it self) its oxidation state is 0.
3) In the right side of the given equation you that iron is now in form of cation with charge 2+: Fe²⁺.
That means that the new oxidation state of the element is 2+.
4) This change in the oxidation state, of course, is accompanied by the loss of the two electrons: 2e⁻.
5) Conclusion: the iron has oxidized by losing two electrons and increasing its oxidation state from 0 to 2+.
<span></span>
D. Hydrogen chemical bonds are found within water molecules.
The freezing point depression of the solution or pure substance that is added with the solvent is calculated through the equation,
ΔTf = Kfm
where ΔT is the freezing point depression, Kf is the constant for water given to be -1.86°C/m and m is the molality of the solution.
Molality is calculated through the equation,
m = number of moles solute/ kg of solvent
Calculation of molality is shown below.
m = (21.5 g C6H12O6)(1 mol/180 g) / (0.255 kg)
m = 0.468 molal
The freezing point depression is then,
ΔTf = (-1.86°C/m)(0.468 m) = -0.87°C
<em>Answer: -0.87°C</em>
