In order to calculate the enthalpy of the reaction, we first calculate the heat released using the given formula.
Q = mc<span>ΔT
Q = 1000 x 4.184 x (35.65 - 24.85)
Q = 45187.2 J = 45.2 kJ
Now, we determine the moles of methane that were burned.
Moles = mass / Mr
Moles = 1.11 / (12 + 4)
Moles = 0.07
The enthalpy of a reaction is the energy released per mole, so the enthalpy in this case is:
</span>ΔH = 45.2 / 0.07
ΔH = 645.7 kJ/mol
Answer:
0.012mol
Explanation:
1.
Given parameters:
Pressure in the balloon = 1.25atm
Volume of the balloon = 2.5L
Unknown:
Number of moles = ?
Solution:
We are going to used the combined gas law to solve this problem.
PV = nRT
P is the pressure
V is the volume
n is the number of moles
R is the gas constant = 0.082atmdm³mol⁻¹K⁻¹
Insert the parameters and solve;
1.25 x 2.5 = n x 0.082 x 285
n = 0.13mol
The number of moles is 0.13mol
2.
Given parameters:
Pressure = 16torr;
to atm is ;
760torr = 1atm
16torr = = 0.02atm
Volume = 12L
Temperature = 253K
Using the ideal gas law;
PV = nRT
0.02x12 = n x 0.082 x 253
n = 0.012mol