Our atmosphere is composed primarily of nitrogen and oxygen, which coexist at 25°c without reacting to any significant extent. however, the two gases can react to form nitrogen monoxide according to the reaction: n2(g) + o2(g) = 2 no(g)

a. calculate agⓡ and k, for this reaction at 298 k. is the reaction spontaneous?
b. estimate agⓡ at 2000 k. does the reaction become more spontaneous as temperature increases?

a) T = 298 K

⇒ ΔG° = 173.1 KJ/mol

∴ ΔG° > 0the reaction occurs spontaneously in the reverse direction as given.

⇒ K = 4.542 E-31

b) T = 2000 K:

⇒ ΔG° = 1161.745 KJ/mol

ΔG°(2000K) > 0; We confirm that the reaction becomes more spontaneous as the temperature increases.

Explanation:

N2(g) + O2(g) → 2 NO(g)

a) ΔG°(298K) = 2 ΔG°fNO = 2(86.55 KJ/mol)

⇒ ΔG°(298K) = 173.1 KJ/mol

∴ ΔG° > 0the reaction is spontaneous

∴ R = 8.314 E-3 KJ/mol.K

⇒ K = e∧(-173.1/(8.314E-3)(298)) = 4.542 E-31

b) T = 2000 K

⇒ ΔG°(2000K) = - (Ln (4.542 E-31))(8.314 E-3 KJ/mol.K)(2000K)

⇒ ΔG°(2000K) = 1161.745 KJ/mol

∴ ΔG°(2000K) > 0; We confirm that the reaction becomes more spontaneous as the temperature increases

b. accuracy of the data matters alot more than its number of digits, organization or amount of detail. quantitative observation is more accepted than the qualitative observation.

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.