1. Questions

Chemistry- Dr. Bob

Question 1
Calculate the wavelength (in nm) of the red light emitted by a neon sign with a frequency of 4.74 x 1014 Hz.


A)

704 nm

B)

158 nm

C)

466 nm

D)

633 nm

E)

142 nm

My answer: D.633 nm

Question 2
How many photons are contained in a burst of yellow light (589 nm) from a sodium lamp that contains 609 kJ of energy?


A)

4.03 x 1028 photons

B)

3.06 x 1030 photons

C)

1.80 x 1024 photons

D)

3.37 x 1019 photons

My answer: C. 1.80 x 10^24 photons (ignore the incorrect ..1024..I meant 10^24)

Question 3

Determine the shortest frequency of light required to remove an electron from a sample of Ti metal, if the binding energy of titanium is 3.14 x 103 kJ/mol.


A)

4.74 x 1015 Hz

B)

6.19 x 1015 Hz

C)

1.27 x 1015 Hz

D)

7.87 x 1015 Hz

E)

2.11 x 1015 Hz

My answer : D 7.87 x 10^15 Hz (again.. ignore the incorrect typing of the exponent)

Question 4

Determine the energy change associated with the transition from n=2 t n=5 in the hydrogen atom.


A)

-2.18 x 10-19 J

B)

6.54 x 10-19 J

C)

4.58 x 10-19 J

D)

-1.53 x 10-19 J

E)

2.18 x 10-19 J

My answer: C 4.58 x 10^/19 J

Question 5

What are the possible values of l if n=6?


A)

-4, -3, -2, -1, 0, +1, +2, +3, +4

B)

-5, -4, -3, -2, -1, 0, +1, +2, +3, +4, +5

C)

0, 1, 2, 3, 4, or 5

D)

6

My answer: C 0,1,2,3,4, or 5