THE EXPLINATION ANSWER: I think crude oil is a mixture because it is made up of compounds that can be separated using distillation, a physical process.
Answer:
Partial pressure of dinitrogen tetroxide after equilibrium is reached the second time is 0.82 atm.
Explanation:

Initially
3.0 atm 0
At equilibrium
(3.0-2p) p
Equilibrium partial pressure of 
p = 0.45 atm
The value of equilibrium constant wil be given by :


After addition of 1.5 atm of nitrogen dioxide gas equilibrium reestablishes it self :

After adding 1.5 atm of
:
(2.1+1.5) atm 0.45 atm
At second equilibrium:'
(3.6-2P) (0.45+P)
The expression of equilibrium can be written as:


Solving for P:
P = 0.37 atm
Partial pressure of dinitrogen tetroxide after equilibrium is reached the second time:
= (0.45+P) atm = (0.45 + 0.37 )atm = 0.82 atm
Partial pressure of dinitrogen tetroxide after equilibrium is reached the second time is 0.82 atm.
We Know, Atomic number of Uranium = 92
Molar mass in given species = 233
Now, Molar mass = Number of Protons + Number of Neutrons
233 = 92 + x
x = 233 - 92
x = 141
So, your final answer is 141
Hope this helps!
Answer:
In Greek it means sphaira or ball which can be related to the Earth,the atmosphere or biosphere.