Answer:
a.
1. NO2(g): Reactant.
2. CO(g): Reactant.
3. NO3(g): Intermediate.
4. CO2(g): Product.
5. NO(g): Product.
b. See attached picture.
Explanation:
Hello,
a. In this case, given the reactions, we can identify each species as:
1. NO2(g): Reactant because it remains at the left side in the overall reaction.
2. CO(g): Reactant because it remains at the left side in the overall reaction.
3. NO3(g): Intermediate because it is a product in the step 1 and a reactant in step 2, for that reason it is not present in the overall reaction.
4. CO2(g): Product because it remains at the right side in the overall reaction.
5. NO(g): Product because it remains at the right side in the overall reaction.
b. In this case, given that the first step is slow and endothermic, it has a high activation energy and the products will have more energy than the reactants, for that reason the final energy is above the initial point. Moreover, since the second step is fast and exothermic, it has a low activation energy and the products will have less energy than the reactants, for that reason, the reaction coordinate diagram is shown on the attached file.
Regards.
Answer: 8.59 L of oxygen gas are needed to produce 100 kJ of energy at STP
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number
of particles.
Standard condition of temperature (STP) is 273 K and atmospheric pressure is 1 atmosphere respectively.
1 mole of every gas occupy volume at STP = 22.4 L
The balanced chemical reaction is:

3909.9 kJ of of energy is produced by = 
100 kJ of oxygen gas are needed to produce = 
It will form HCN Hydrogen Cyanide.
The elements that form anions will have the electronic configuration similar to the noble gas that is in their period and those that form cations will have a configuration similar to that of the noble gas in the previous period.
He: Be
Ne: F, Al
Ar: Ca, P
Kr: Rb, Se
P and S
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