Answer is b. Hope it help
Answer:
The change in the internal energy of the system -878 J
Explanation:
Given;
energy lost by the system due to heat, Q = -1189 J (negative because energy was lost by the system)
Work done on the system, W = -311 J (negative because work was done on the system)
change in internal energy of the system, Δ U = ?
First law of thermodynamics states that the change in internal energy of a system (ΔU) equals the net heat transfer into the system (Q) minus the net work done by the system (W).
ΔU = Q - W
ΔU = -1189 - (-311)
ΔU = -1189 + 311
ΔU = -878 J
Therefore, the change in the internal energy of the system -878 J
Answer:
See explanation
Explanation:
For a reaction that proceeds by E1 mechanism, the rate determining step involves the formation of the carbocation.
The rate of formation of this carbocation depends only on the concentration of the t-butyl bromide since it is the only specie that enters into the rate equation.
Hence, when the concentration of t-butyl bromide is tripled, the rate of reaction is tripled.
Methanol does not enter into the rate equation hence doubling its concentration does not affect the rate of reaction.
Answer:
The volume of the vessel is 250 L
Partial pressure of hydrogen = 189 torr
Explanation:
Using Boyle's law
![{P_1}\times {V_1}={P_2}\times {V_2}](https://tex.z-dn.net/?f=%7BP_1%7D%5Ctimes%20%7BV_1%7D%3D%7BP_2%7D%5Ctimes%20%7BV_2%7D)
Given ,
V₁ = 20.0 L
V₂ = ?
P₁ = 25 atm
P₂ = 2 atm
Using above equation as:
![{P_1}\times {V_1}={P_2}\times {V_2}](https://tex.z-dn.net/?f=%7BP_1%7D%5Ctimes%20%7BV_1%7D%3D%7BP_2%7D%5Ctimes%20%7BV_2%7D)
![{25}\times {20.0}={2}\times {V_2}](https://tex.z-dn.net/?f=%7B25%7D%5Ctimes%20%7B20.0%7D%3D%7B2%7D%5Ctimes%20%7BV_2%7D)
![{V_2}=\frac {{25}\times {20.0}}{2}\ L](https://tex.z-dn.net/?f=%7BV_2%7D%3D%5Cfrac%20%7B%7B25%7D%5Ctimes%20%7B20.0%7D%7D%7B2%7D%5C%20L)
![{V_2}=250\ L](https://tex.z-dn.net/?f=%7BV_2%7D%3D250%5C%20L)
<u>The volume of the vessel is 250 L.</u>
According to Dalton's law of partial pressure:-
![P_{H_2}=Mole\ fraction\times Total\ Pressure](https://tex.z-dn.net/?f=P_%7BH_2%7D%3DMole%5C%20fraction%5Ctimes%20Total%5C%20Pressure)
So, according to definition of mole fraction:
![Mole\ fraction\ of\ H_2=\frac {n_{H_2}}{n_{H_2}+n_{He}}](https://tex.z-dn.net/?f=Mole%5C%20fraction%5C%20of%5C%20H_2%3D%5Cfrac%20%7Bn_%7BH_2%7D%7D%7Bn_%7BH_2%7D%2Bn_%7BHe%7D%7D)
Also,
Mole fraction of H₂ = 1 - Mole fraction of He = 1 - 0.75 = 0.25
So,
Total pressure = 756 torr
Thus,
![P_{H_2}=0.25\times 756\ torr](https://tex.z-dn.net/?f=P_%7BH_2%7D%3D0.25%5Ctimes%20756%5C%20torr)
<u>Partial pressure of hydrogen = 189 torr.</u>