Complete Question
The complete question is shown on the first uploaded image
Answer:
The concentration of
that should used originally is 
Explanation:
From the question we are told that
The necessary elementary step is

The time taken for sixth of 0.5 M of reactant to react 
The time available is 
The desired concentration to remain
Let Z be the reactant , Y be the first product and X the second product
Generally the elementary rate law is mathematically as

Where k is the rate constant ,
is the concentration of Z
From the elementary rate law we see that the reaction is second order (This because the concentration of the reactant is raised to power 2 )
For second order reaction

Where
is the initial concentration of Z which a value of 
From the question we are told that it take 9 hours for the concentration of the reactant to become


So


=> 
For 





Answer:

Explanation:
Potential energy is energy due to position. It is the product of mass, height, and acceleration due to gravity.

The mass of the textbook is 1.85 kilograms. Assuming this is on Earth, the acceleration due to gravity is 9.8 meters per square second. The height is 2.23 meters.
- m= 1.85 kg
- g= 9.8 m/s²
- h= 2.23 m
Substitute the values into the formula.

Multiply the first 2 numbers together.

Multiply again.

- 1 kilogram square meter per square second (1 kg*m²/s²) is equal to 1 Joules (J)
- Our answer of 40.4299 kg*m²/s² is equal to 40.4299 J

The textbook has <u>40.4299 Joules of potential energy.</u>
If the two gases has a total pressure of 5.7 atm and one of the gases has a partial pressure of 4.1 the the other one has the pressure of 1.6
I suppose that the answer is A