Answer:
-1190.24 kJ
Explanation:
The enthalpy change in a chemical reaction that produces or consumes gases is given by the expression:
ΔH = ΔU + Δngas RT
where Δn gas is the change of moles of gas, R is the gas constant,and T is temperature.
Now from the given balanced chemical reaction, the change in number of mol gas is equal to:
Δn gas = mole gas products - mole gas reactants = 2 - 5/2 = -1/2 mol
Sionce we know ΔU and the temperature (298 K), we are in position to calculate the change in enthalpy.
ΔH = -1189 x 10³ J + (-0.5 mol ) 8.314 J/Kmol x 298 K
ΔH = -1.190 x 10⁶ J = -1.190 x 10⁶ J x 1 kJ/1000 J = -1.190 x 10³ J
The beast tenth is 2 cause it’s close to both
Answer:
140. J/g*K
Explanation:
To find the specific heat capacity, you need to use the following equation:
Q = mcΔT
In this equation,
-----> Q = energy/heat (J)
-----> m = mass (g)
-----> c = specific heat (J/mole*K)
-----> ΔT = change in temperature (K)
Before you can use the equation above, you need to (1) convert kg to grams, then (2) convert grams to moles (via molar mass), and then (3) convert Celsius to Kelvin. The final answer should have 3 significant figures.
1.11 kg C₄H₈O₂ x 1,000 = 1110 g
Molar Mass (C₄H₈O₂): 4(12.01 g/mol) + 8(1.008 g/mol) + 2(16.00 g/mol)
Molar Mass (C₄H₈O₂): 88.104 g/mol
1110 grams C₄H₈O₂ 1 mole
------------------------------ x ------------------------- = 12.6 moles C₄H₈O₂
88.104 grams
34.5 °C + 273 = 307.5 K
52.3 °C + 273 = 325.3 K
Q = mcΔT <----- Equation
3.14 x 10⁴ J = (12.6 moles)c(325.3 K - 307.5 K) <----- Insert values
3.14 x 10⁴ J = (12.6 moles)c(17.8) <----- Subtract
3.14 x 10⁴ J = (224.28)c <----- Multiply 12.6 and 17.8
140. = c <----- Divide both sides by 224.28
**this answer may be slightly off due to using different molar masses/Kelvin conversions**