Answer:
Hello your question is poorly written below is the well written question
Uranium, an important component of both nuclear weapons and nuclear reactors, has two major isotopes, U-238, which has a half-life of approximately 4.5 billion years, and U-235, which has a half-life of approximately 700 million years. Both were present in equal amounts at the time of the creation of the Earth, 4.5 billion years ago. How many years after the creation of the Earth had the amount of radiation from uranium decayed to half the amount present at the time of the creation of the Earth
Answer : 140 billion years
Explanation:
Given that :
U-238 h1/2 = 4.5 billion years
U-235 h1/2 = 700 million years
At the beginning both Isotopes where present in equal amount
Determine the T years before the amount of Uranium decays to Half
T = ? N'2 = N1 / 2
we know that N = No ( 1/2 )^h where h = time / half-life time
attached below is the detailed solution of the given problem
The given question is incomplete. The complete question is:
The change in entropy is related to the change in the number of moles of gas molecules. Determine the change in moles of gas for each of the reactions and decide if the entropy increases decreases or has little to no change:
A. 
B. 
C. 
D.
Answer: A.
: decreases
B.
: decreases
C.
: no change
D.
: increases
Explanation:
Entropy is defined as the randomness of the system.
Entropy is said to increase when the randomness of the system increase, is said to decrease when the randomness of the system decrease and is said to have no change when the randomness remains same.
In reaction
, as gaseous reactant is changed to solid product, entropy decreases.
In reaction
, as 4 moles of gaseous reactants is changed to 2 moles of gaseous product, entropy decreases.
In reaction
, as 3 moles of gaseous reactants is changed to 3 moles of gaseous product, entropy has no change.
In reaction
, as 1 mole of gaseous reactant is changed to 3 moles of gaseous product, entropy increases.
Answer: Partial pressure of
at a depth of 132 ft below sea level is 2964 mm Hg.
Explanation:
It is known that 1 atm = 760 mm Hg.
Also, 
where,
= partial pressure of 
P = atmospheric pressure
= mole fraction of 
Putting the given values into the above formula as follows.


= 0.780
Now, at a depth of 132 ft below the surface of the water where pressure is 5.0 atm. So, partial pressure of
is as follows.

= 
= 2964 mm Hg
Therefore, we can conclude that partial pressure of
at a depth of 132 ft below sea level is 2964 mm Hg.