calculation qu (1 Viewer)

[sikeveo]

Determine the velocity and frequency of the electron in the ground state of the hydrogen atom, whose wavelength is 5.3 x 10 ^(-11) metres

 

[serge]

Determine the velocity and frequency of the electron in the ground state of the hydrogen atom, whose wavelength is 5.3 x 10 ^(-11) metres

lambda = nh/mv n is 1 (ground state)

too lazy to get a calculator

 

[darkwarrior2]

if c = f x wavelength then sub wavelength into it and find f.
not sure about velocity, id like to know this too.

 

[serge]

if c = f x wavelength then sub wavelength into it and find f.
not sure about velocity, id like to know this too.

ooh... but they said electron, not photon...

 

[darkwarrior2]

god im screwed if they ask this shit in the exam lol, but i dont recall that formula being in the formula book either .

 

[richz]

u get the velocity by using the eqn lambda=h/mv
sub in wavelength, mass of electron and h is plancks constant

 

[serge]

god im screwed if they ask this shit in the exam lol, but i dont recall that formula being in the formula book either .

they dont have to give you each one...
plenty of the formulas are missing

(i think you can derive the one i mentioned
from the bohr equation?)

 

[Captain Gh3y]

u were right the first time. v is not c, since it's an electron, so you have to get the velocity first.

λ = h/mv

5.3x10^-11 = 6.626x10^-34 / (9.109x10^-31 x v)

v = 6.626x10^-34 / (6.626x10^-34 x 5.3x10^-11)

v = 1.372x10⁷ms^-1 (3dp)

Now v = fλ

1.3725.3x10⁷ = f x 5.3x10^-11

f = 1.3725x10⁷ / 5.3x10^-11

f = 2.59x10¹⁷ Hz (3dp)