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:
THE EMPIRICAL FORMULA FOR THE UNKNOWN COMPOUND IS C7H9O
Explanation:
The empirical formula for the unknown compound can be obtained by following the processes below:
1 . Write out the percentage composition of the individual elements in the compound
C = 75.68 %
H = 8.80 %
O = 15.52 %
2. Divide the percentage composition by the atomic masses of the elements
C = 75 .68 / 12 = 6.3066
H = 8.80 / 1 = 8.8000
O = 15.52 / 16 = 0.9700
3. Divide the individual results by the lowest values
C = 6.3066 / 0.9700 = 6.5016
H = 8.8000 / 0.9700 = 9.0722
O = 0.9700 / 0.9700 = 1
4. Round up the values to the whole number
C = 7
H = 9
O = 1
5 Write out the empirical formula for the compound
C7H90
In conclusion, the empirical formula for the unknown compound is therefore C7H9O
The correct answer is + 32.5 J because heat is absorbed here by copper not evolved also after calculation we will find the H value is positive, lets calculate it:
H = m C Δt where:
m = 10 g
C = 0.13 J/g.°C
Δ t = final temperature - initial temperature = 50 - 25 = + 25 °C
so H = 10 x 0.13 x (+25) = + 32.5 J
Answer:
Ok to solve this you will need to use the Ideal Gas Law Formula which is as follows:
PV = nRT
P= pressure
V= volume
n= # of moles
R= Universal Gas Constant (0.0821 L x atm/mol x K)
T= Kelvin temperature
1.Simplify the Ideal Gas Law formula to what you need to solve for:
P = (nRT)/ V
2. List all you components as follows (this makes the process easier):
P = ?
V = 45.4 L
n = 0.625 mol
R = 0.0821 L x atm/ mol x K
T = 249 K
To find the Kelvin temperature K = C + 273
3. Plug in all your components in your set up formula:
P = [(0.625 mol)(0.0821 L x atm/ mol x K)(249 K)] / (45.4 L)
4. Cross out all similar units so the only thing left is atm because you are trying to find pressure.
P = [(0.625)(0.0821atm)(249)] / (45.4)
5. Multiply through and simplify
P = 0.28 atm
B. is the correct answer.
Glad I could help!! If you have any other questions just message me. Hopefully this was helpful.
Explanation:
