Answer:fH = - 3,255.7 kJ/mol
Explanation:Because the bomb calorimeter is adiabatic (q =0), there'is no heat inside or outside it, so the heat flow from the combustion plus the heat flow of the system (bomb, water, and the contents) must be 0.
Qsystem + Qcombustion = 0
Qsystem = heat capacity*ΔT
10000*(25.000 - 20.826) + Qc = 0
Qcombustion = - 41,740 J = - 41.74 kJ
So, the enthaply of formation of benzene (fH) at 298.15 K (25.000 ºC) is the heat of the combustion, divided by the number of moles of it. The molar mass od benzene is: 6x12 g/mol of C + 6x1 g/mol of H = 78 g/mol, and:
n = mass/molar mass = 1/ 78
n = 0.01282 mol
fH = -41.74/0.01282
fH = - 3,255.7 kJ/mol
A 1. 00 ml sample of an unknown gas effuses in 11. 1 min. an equal volume of h2 in the same apparatus under the same conditions effuses in 2. 42 minutes then the molar mass of the unknown gas is 41.9.
Molar mass of H2 = 2
Molar mass of unknown gas = ?
rate 1 = 11.1
rate 2 = 2.42
<h3>What is graham law? </h3>
Graham's law states that the rate of diffusion or effusion of a given gas is inversely proportional to the square root of its molar mass.
By apply graham law
Rate1/rate2 = sqrt(MW2/MW1)
![[\frac{rate1}{rate2} ]^{2} = \frac{MW2}{2} \\\\\\mw= 2[\frac{11.1}{2.42} ]^{2} \\\\= 20.97 X 2 \\\\= 41.9](https://tex.z-dn.net/?f=%5B%5Cfrac%7Brate1%7D%7Brate2%7D%20%5D%5E%7B2%7D%20%3D%20%5Cfrac%7BMW2%7D%7B2%7D%20%5C%5C%5C%5C%5C%5Cmw%3D%202%5B%5Cfrac%7B11.1%7D%7B2.42%7D%20%5D%5E%7B2%7D%20%5C%5C%5C%5C%3D%2020.97%20X%202%20%5C%5C%5C%5C%3D%2041.9)
Thus, we found that the molar mass of the unknown gas is 41.9.
Learn more about graham's law: brainly.com/question/12415336
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Answer:
The longer it takes to orbit the sun.
Explanation:
Answer: Physical changes are related to physical properties since some measurements require that changes be made. Melting Point: As solid matter is heated it eventually melts or changes into a liquid state at the melting point. Ice (a solid form of water) melts at 0 oC and changes to the liquid state.
Explanation:
