Answer:
T = 377.2 K, Less than
Explanation:
The thermodynamic quantity used in predicting whether a reaction is spontaneous or not is the gibbs free energy.
It's relationship with ΔH⁰ and ΔS⁰ is given as;
ΔG° = ΔH° - TΔS°
Basically, a negative value of ΔG° means the reaction is spontaeneous.
To obtain the calculated vale of T,
ΔS° = ΔH°/T
T = ΔH° / ΔS°
T = 377.2 K
Let's calculate the value of ΔG° at that temperature.
ΔG° = ΔH° - TΔS°
ΔG° = − 46700 - 377.2(− 123.8)
ΔG° = 0 (approximately, values are due to the rounding off)
At ΔG° = 0 the reaction is at equilibrium.
To find if the reaction is spontaneous at lower or hugher temperature than the calculated temperature, we would be substituting the value of T with a smaller (random) value and also a larger (random) value.
Larger T (390K)
ΔG° = ΔH° - TΔS°
ΔG° = − 46700 - 390(− 123.8)
ΔG° = - 46700 + 48,282
ΔG° = 1582 J/mol
Smaller T (350K)
ΔG° = ΔH° - TΔS°
ΔG° = − 46700 - 350(− 123.8)
ΔG° = - 46700 + 43330
ΔG° = -3370J/mol
This means the temperature would be lesser than the calculated value for it to be spontaneus.
Answer:
Volume of N₂ = 14.76 L
Volume of H₂ = 29.52 L
Explanation:
Given data:
Mass of N₂H₄ formed = 28.5 g
Pressure = 1.50 atm
Temperature = 30°C (30+273 = 303 k)
Volume of N₂ and H₂ needed = ?
Solution:
Chemical equation:
N₂ + 2H₂ → N₂H₄
Number of moles of N₂H₄ formed = mass/ molar mass
Number of moles of N₂H₄ formed = 28.5 g/ 32 g/mol
Number of moles of N₂H₄ formed = 0.89 mol
Now we will compare the moles of N₂H₄ with N₂ and H₂ form balance chemical equation.
N₂H₄ : N₂
1 : 1
0.89 : 0.89
N₂H₄ : H₂
1 : 2
0.89 : 2×0.89 = 1.78 mol
Volume of H₂:
PV = nRT
1.50 atm × V = 1.78 mol × 0.0821 atm.L/mol.K × 303 K
V = 44.28atm.L /1.50 atm
V = 29.52 L
Volume of N₂:
PV = nRT
1.50 atm × V = 0.89 mol × 0.0821 atm.L/mol.K × 303 K
V = 22.14 atm.L /1.50 atm
V = 14.76 L
I think it is A if wrong I’m sorry
