<span>The problem has to do with oxidation states of the matter. The oxidation state of oxygen will always be -2 with the exception of peroxides which will have a state of -1. The overall balanced state of chemical compounds will be 0, so the oxidation state of Mn in MnO2 will be +4. The oxidation state of MnO4- will then be +7 to balance out to the negative one charge. The state change from +4 to +7 is 3, thus three electrons have to be lost in order for this to happen; a loss of a charge of -3 results in an increase of charge of 3. Oxidation is always the process of 'losing' electrons.
</span><span>E] MnO2(s) MnO4-(aq</span>
Increase, because you need heat to melt a solid to a liquid, so the temperature will have to get greater.
The mole ratio would be 2:2:2
Answer:

Explanation:
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In this case, since the thermodynamic definition of the Gibbs free energy for a change process is:

It is possible to plug in the given H, T and S with consistent units, to obtain the correct G as shown below:

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