D) Sulphur i think thats correct
Answer:

-) Oxidizing agent: 
-) Reducing agent: 
Explanation:
The first step is separate the reaction into the <u>semireactions</u>:
A.
B.
If we want to balance in <u>basic medium </u>we have to follow the rules:
1. We adjust the oxygen with 
2. We adjust the H with 
3. We adjust the charge with 
Lets balance the first semireaction A. :

Now, lets balance semireaction B:

Finally, we have to add the two semireactions:
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Cancel out the species on both sides:

Simplifying the equation :

The
is <u>oxidized</u> therefefore is the <u>reducing agent</u>. The
is<u> reduced</u> therefore is the <u>oxidizing agent</u>.
Answer: "The reactants are higher in energy than the products"
Explanation:
The exothermic reactions are characterized by the release of heat to the surroundings. The reactants lose heat that is delivered to the surroundings which implies that the products will be lower in energy than the reactants.
The hills that you can see in a reaction energy diagram are not related with the final change of energy. The hills are an indication of the activation energy needed to start the reaction, but they do not measure the change of energy from the products to the reactants.
The enthalpy that is a state variable that identifies the content of heat. Then the change of enthalpy for the exothermic reactions is negative, meaning that the energy of the products is lower than the energy of the reactants.
The common neutralization reaction that involve NaOH reacting with HNO3 produces
NaNO3 and H2O
The equation for reaction is as folows
NaOH + HNO3 = NaNO3 + H2O
that is 1 mole of NaOH reacted with 1 mole of HNO3 to form 1 mole of NaNO3 and 1 mole of H2O