Answer:
-973 KJ
Explanation:
The balanced reaction equation is;
N2H4(aq) + 2Cl2(g) + 4OH^-(aq)---------> 4Cl-(aq) + 4H ^+(aq) + 4OH^-(aq) + N2(g)
Reduction potential of hydrazine = -1.16 V
Reduction potential of chlorine = 1.36 V
From;
E°cell= E°cathode - E°anode
E°cell= 1.36 - (-1.16)
E°cell= 2.52 V
∆G°=- nFE°cell
n= number of moles of electrons = 4
F= Faraday's constant = 96500 C
E°cell = 2.52 V
∆G°=- (4 × 96500 × 2.52)
∆G°= -972720 J
∆G°= -972.72 KJ
Answer:
A. m C5H12 = 108.23 g
B. m F2 = 547.142 g
C. m Ca(CN)2 = 71.85 g
Explanation:
- mass (m) = mol (n) × molecular weigth (Mw)
∴ Mw C5H12 = ((12.011)(5)) + ((1.008)(12)) = 72.151 g/mol C5H12
∴ Mw F2 = (18.998)(2) = 37.996 g/mol F2
∴ Mw = Ca(CN)2 = 40.078+((12.011+14.007)(2)) = 92.114 g/mol Ca(CN)2
A. m C5H12 = ( 1.50 mol)×(72.151 g/mol) = 108.23 g C5H12
B. m F2 = (14.4 mol)×(37.996 g/mol) = 547.142 g F2
C. m Ca(CN)2 = (0.780 mol)×(92.114 g/mol) = 71.85 g Ca(CN)2
Explanation:
1. Thermochemical equation is balance stoichiometric chemical equation written with the phases of the reactants and products in the brackets along with the enthalpy change of the reaction.
The given correct thermochemical reactions are:
2. Phase change affect the value of the enthalpy change of the thermochemical equation. This is because change in phase is accompanied by change in energy. For example:
In both reaction phase of water is changing with change in energy of enthalpy of reaction.
Answer:
131.5 kJ
Explanation:
Let's consider the following reaction.
CaCO₃(s) → CaO(s) + CO₂(g)
First, we will calculate the standard enthalpy of the reaction (ΔH°).
ΔH° = 1 mol × ΔH°f(CaO(s)) + 1 mol × ΔH°f(CO₂(g)
) - 1 mol × ΔH°f(CaCO₃(s)
)
ΔH° = 1 mol × (-634.9 kJ/mol) + 1 mol × (-393.5 kJ/mol) - 1 mol × (-1207.6 kJ/mol)
ΔH° = 179.2 kJ
Then, we calculate the standard entropy of the reaction (ΔS°).
ΔS° = 1 mol × S°(CaO(s)) + 1 mol × S°(CO₂(g)
) - 1 mol × S°(CaCO₃(s)
)
ΔS° = 1 mol × (38.1 J/mol.K) + 1 mol × (213.8 J/mol.K) - 1 mol × (91.7 J/mol.K)
ΔS° = 160.2 J/K = 0.1602 kJ/K
Finally, we calculate the standard Gibbs free energy of the reaction at T = 25°C = 298 K.
ΔG° = ΔH° - T × ΔS°
ΔG° = 179.2 kJ - 298 K × 0.1602 kJ/K
ΔG° = 131.5 kJ
LMBO, for science.
Answer:
<em>The increase in kinetic energy leads to leakage of water from the syringe. When the outside temperature is more than the liquid temperature, say the syringe is out in sunshine, then the liquid becomes slightly warmer.</em>
