Need clarification on any questions before your trial HSC? ASK ME!! (1 Viewer)

[Fizzy_Cyst]

^^ what the thread title says.

or PM me

 

[Aindan]

Hey mate,

can you explain the significance of Bohr's third postulate and how exactly that it determines the allowed stationary orbits?

 

[Fizzy_Cyst]

Bohrs Third Postulate states that the electrons angular momentum is quantised, such that , where n is the principal energy shell number. Bohr himself could not explain why the electrons angular momentum was quantised, it was merely a condition for his model of the atom to actually work.

It was not until De Broglie came along with the idea of 'matter waves' that Bohr's first postulate could actually be explained, rather than just stated and De Broglie was the main person responsible for giving credibility to the Bohr model of the atom.

De Broglie suggested that electrons exist in the stationary states when they form standing waves around the nucleus of an atom, a standing wave occurs when there is an integral multiple of wavelengths of the electron around the circumference of the electron orbits.



Using De Broglies relationship between matter and waves (which he derived from equating and )




multiplying both sides by an integral multiple 'n'


Using the first equation relating circumference and wavelength


Rearranging to make angular momentum the subject


Which agreed with Bohr's third postulate. Thus, De Broglies idea of matter waves could be used to explain Bohr's first postulate and mathematically prove Bohrs third postulate.

 

[Bobbo1]

What is the difference between adapative and active optics in astro??

 

[Rage_Quitter]

Where is it possible to find questions that are from topic to topic? (I don't know if this is related)

 

[Aindan]

Bohrs Third Postulate states that the electrons angular momentum is quantised, such that , where n is the principal energy shell number. Bohr himself could not explain why the electrons angular momentum was quantised, it was merely a condition for his model of the atom to actually work.

It was not until De Broglie came along with the idea of 'matter waves' that Bohr's first postulate could actually be explained, rather than just stated and De Broglie was the main person responsible for giving credibility to the Bohr model of the atom.

De Broglie suggested that electrons exist in the stationary states when they form standing waves around the nucleus of an atom, a standing wave occurs when there is an integral multiple of wavelengths of the electron around the circumference of the electron orbits.



Using De Broglies relationship between matter and waves (which he derived from equating and )




multiplying both sides by an integral multiple 'n'


Using the first equation relating circumference and wavelength


Rearranging to make angular momentum the subject


Which agreed with Bohr's third postulate. Thus, De Broglies idea of matter waves could be used to explain Bohr's first postulate and mathematically prove Bohrs third postulate.

Oh i see! So Bohr's third postulate was actually the result of De Broglie's proposal. And since De Broglie's proposal said that the circumference must be equal to integer multiples of electron wavelengths, this determined the radius and stuff of each electron orbit...thanks!