An electron that is confined to x Ú 0 nm has the normalized wave function c1x2 = b 0 x 6 0 nm 11.414 nm-1/2 2e-x/11.0 nm2 x Ú 0 nm where x is in nm. a. What is the probability of finding the electron in a 0.010-nmwide region at x = 1.0 nm? b. What is the probability of finding the electron in the interval 0.50 nm … x … 1.50 nm?

Short Answer

Expert verified

Here ψxis the probability amplitude and the complex conjugate of the probability amplitude

Step by step solution

01

To find the probability amptitude

The wave ψxis the probability of finding particle at a given point x the article probability of finding the particle in a region by the product of the wave function with is complex

The expression of the probability of the normalized wave function is

p=x1x2ψ*xψx

02

(a)The electron is in a 0.01 nm wide region and the probability at x=1.0nm is to be calculated the region in which the electron is moving in this case 

x1=x-x2

and

x1=x+x2

substitute 0.01nm for xand 1nm, for X in the above expression to find the limits

x1=1nm-0.012nm=0.995nm

and,

x2=1nm+0.012nm=1.005nm

The expression of the probability of a normalized wavefunction is given as follows

role="math" localid="1649741312917" P=x1x2ψ*xψxdx

Substitute 1.414nme-x1.0nmfor ψxand ψx,1.005nm for x1 and 0.995 nm for x2 in the above expression

P=0.995nm1.005nm1.414nm12-xe1.0nm1.414nm12-xe1.0nmdx=2.00nm-10.995nm1.005nme2x1.0nmdx=2.00nm-1e-2x1.0nm-21.0nm=-e-2x1.0nm

Substitute the limits and find the value of probability

P=-e21.005nm1.0nm-e20.995nm1.0nm=-0.1339886-0.1366954=0.002706

In percentage:

%P=Px100%

substitute 0.002706 in P in the above expression

%P=(0.002706)x100%

=0.27%

Thus the probability of finding a particle in the region 1nm is 0.27%

03

(b)The expression of the probability of a normalized wavefunction is given as follows

P=x1x2ψ*xψxdx

Substitute 1.414nme-x1.0nmfor ψxand ψx,1.005nm for x1 and 0.995 nm for x2 in the above expression

P=0.5nm1.5nm1.414nm12-xe1.0nm1.414nm12-xe1.0nmdx=2.00nm-10.995nm1.005nme2x1.0nmdx=2.00nm-1e-2x1.0nm-21.0nm=0.25-e-2x1.0nm

substitute the limits and find the value of probability

P=-e21.5nm1.0nm-e20.5nm1.0nm=-0.049787-0.367879=0.318

In percentage:

%P=Px100%

substitute 0.002706 in P in the above expression

%P=(0.318)x100%

=32%

Thus the probability of finding a particle in the region 1nm is 32%

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