Question 281: Atoms & Nuclei

Question

Radiation coming from transitions
n = 2 to n = 1 of hydrogen atoms fall on He+
ions in n = 1 and n = 2 states. The possible
transition of helium ions as they absorb energy
from the radiation is :

Accepted Answer

Energy released for tension n = 2 to n = 1 of hydrogen atom
$$E = 13.6{Z^2}\left( {{1 \over {n_1^2}} - {1 \over {n_2^2}}} ight)$$
Z = 1, n
1
= 1, n
2
= 2
$$E = 13.6 	imes 1 	imes \left( {{1 \over {{1^2}}} - {1 \over {{2^2}}}} ight)$$
$$E = 13.6 	imes {3 \over 4}eV$$ = 10.2 eV
For He
+
ion z = 2
(A) n = 1 to n = 4
$$E = 13.6 	imes {2^2} 	imes \left( {{1 \over {{1^2}}} - {1 \over {{4^2}}}} ight) = 13.6 	imes {{15} \over 4}eV$$
(B) n = 2 to n = 4
$$E = 13.6 	imes {2^2} 	imes \left( {{1 \over {{2^2}}} - {1 \over {{4^2}}}} ight) = 13.6 	imes {{3} \over 4}eV$$
(C) n = 2 to n = 5
$$E = 13.6 	imes {2^2} 	imes \left( {{1 \over {{2^2}}} - {1 \over {{5^2}}}} ight) = 13.6 	imes {{21} \over 25}eV$$
(D) n = 2 to n = 3
$$E = 13.6 	imes {2^2} 	imes \left( {{1 \over {{2^2}}} - {1 \over {{3^2}}}} ight) = 13.6 	imes {{5} \over 9}eV$$
So, possible transition is n = 2 $$	o$$ n = 4

Answer

n = 1 $$ 	o $$ n = 4

Answer

n = 2 $$ 	o $$ n = 5

Answer

n = 2 $$ 	o $$ n = 4

Answer

n = 2 $$ 	o $$ n = 3

Atoms & Nuclei

Radiation coming from transitions n = 2 to n = 1 of hydrogen atoms fall on He+ ions in n = 1 and n = 2 states. The possible transition of helium ions as they absorb energy from the radiation is :

Choose the correct answer: