Answer:
C
Explanation:
A physical change is when the form of the matter is just altered. While a chemical change results from a chemical reaction. No reaction is happening during the mixing of the two colors [nothing is boiling, freezing, evaporating, melting ext.] , but after you mix them the end result does look different. That only because we changed the physical properties of it.
(B is not a physical change because the baking powder inside of the cake must under go a reaction that causes the cake to rise. )
The answer is oxidation.
That is in the redox fueling reaction,
succinate + NAD ↔fumarate + NADPH, the succinate molecule is undergoing oxidation.
As succinate molecule is providing electrons to NAD, so that it can be reduced from NAD to NADPH. So it is losing electrons and undergoing oxidation.
So the answer is oxidation.
For cations, the loss of an electron leaves them with a net positive charge, whereas for anions, the addition of an electron leaves them with a net negative charge. Understanding the processes behind this, including the ionization energy and electron affinity of different atoms, helps you see why certain atoms become ions more easily than others and what causes it to happen.