Answer:
Explanation:
The given reaction is exothermic . So ΔH is negative .
Gas is evolving so work done by gas is positive or w is positive.
Change in internal energy that is ΔU is negative.
q = u - w
u is negative , w is positive so q is negative .
It would be 5.0 more in i did this
Answer:B) a reactant that undergoes reduction
Explanation:
Oxidation reaction is defined as the reaction in which a substance looses electrons. The oxidation state of the substance increases during oxidation.
Reduction reaction is defined as the reaction in which a substance gains electrons. The oxidation state of the substance gets reduced during reduction.

Overall reaction: 
The substance M which itself gets oxidized, reduces other and is called as reducing agent. The substance N which itself gets reduced, oxidizes other and is called as oxidizing agent.