Thank you for registering.

One of our academic counsellors will contact you within 1 working day.

Please check your email for login details.
MY CART (5)

Use Coupon: CART20 and get 20% off on all online Study Material

ITEM
DETAILS
MRP
DISCOUNT
FINAL PRICE
Total Price: Rs.

There are no items in this cart.
Continue Shopping

TOPIC: NIELS BOHR’S ATOMIC MODEL 1 . ​ According to the Bohr’s orbit model, electrons may be present at any of the allowed orbits whose energy is defined by the expression: E n = -2.179 x 10 -18 J(Z 2 / n 2 ), where Z is the atomic number or nuclear charge, and n = 1, 2, 3, .. is called the quantum number . For hydrogen atom that has Z = 1, the energy of the first four orbits are given below: ​ —————————————————————————— ​ Quantum # ​ ​ Energy values _____ ____________ ​ n = 1 ​ ​ ​ -2.18 x 10 -18 J ( lowest energy level or “ ground state ”) ​ n = 2 ​ ​ ​ -5.45 x 10 -19 J ( first excited state ) ​ n = 3 ​ ​ ​ -2.42 x 10 -19 J ( second excited state ) ​ n = 4 ​ ​ ​ -1.36 x 10 -19 J ( third excited state ) ​ —————————————————————————— (Speed of light, c = 2.998 x 10 8 m/ s; h = 6.626 x 10 -34 J.s. ; 1 nm = 10 -9 m; 1 m = 10 9 nm) (a) Why are the energy values negative? (b) An electron in hydrogen atom jumps from the first orbit ( n = 1) to the 4 th orbit ( n = 4). What is the energy change (  E) for the electron? Does the electron gain or lose energy? Explain. What are the frequency (  ) and wavelength (  ) of light that would provide just enough energy for the electron to make this jump? In what spectral region is this light found, uv , visible, or infra-red region? (c) The same electron then jumps from the 4 th orbit to the second orbit ( n = 2). What is the energy change (  E) for the electron in this jump? Does the electron gain or lose energy? Explain. What are the frequency (  ) and wavelength (  ) of light emitted from this energy change? In what spectral region is this light emitted, uv , visible, or infra-red region?

 

 

TOPIC: NIELS BOHR’S ATOMIC MODEL

1.According to the Bohr’s orbit model, electrons may be present at any of the allowed orbits whose energy is defined by the expression: En = -2.179 x 10-18 J(Z2/n2), where Z is the atomic number or nuclear charge, and n = 1, 2, 3, ..is called the quantum number. For hydrogen atom that has Z = 1, the energy of the first four orbits are given below: 

——————————————————————————

Quantum #    Energy values_________________

n = 1-2.18 x 10-18 J  (lowest energy level or “ground state”)

n = 2-5.45 x 10-19 J  (first excited state)

n = 3-2.42 x 10-19 J  (second excited state)

n = 4-1.36 x 10-19 J  (third excited state)

——————————————————————————

(Speed of light, c = 2.998 x 108 m/s;  h = 6.626 x 10-34 J.s.;  1 nm = 10-9 m;  1 m = 109 nm)

 

(a) Why are the energy values negative?  

 

 

 

(b) An electron in hydrogen atom jumps from the first orbit (n = 1) to the 4th orbit (n = 4). What is the energy change (E) for the electron? Does the electron gain or lose energy? Explain. What are the frequency () and wavelength () of light that would provide just enough energy for the electron to make this jump? In what spectral region is this light found, uv, visible, or infra-red region?

 

 

 

      

 

(c) The same electron then jumps from the 4th orbit to the second orbit (n = 2). What is the energy change (E) for the electron in this jump? Does the electron gain or lose energy? Explain. What are the frequency () and wavelength () of light emitted from this energy change? In what spectral region is this light emitted, uv, visible, or infra-red region?

Grade:12th pass

1 Answers

Avni Chauhan
askIITians Faculty 247 Points
3 years ago
Please ask seperate questions in seperate threads.

Energy outside an atom of an electron is considered to be zero, outside of all the fields.
But inside an atom the electron should be more stable considering the fact that its near the nucleaus. Now we know as stability increases, energy decreases. And only a negative number can be less than zero. Hence electrons have a negative energy.

Think You Can Provide A Better Answer ?

Provide a better Answer & Earn Cool Goodies See our forum point policy

ASK QUESTION

Get your questions answered by the expert for free