9. Electron spin

Question 1

Define spin

Answer 1

An intrinsic angular momentum an electron carries

Question 2

What is the spin of an electron?

Answer 2

1/2

Question 3

What is the symbol for the spin angular momentum?

Answer 3

S

Question 4

See page 4 on document for spin diagram

Answer 4

Do it lmao

Question 5

Give the equation for the z component of the angular momentum with spin

Answer 5

L_z = m_s*h_bar

Question 6

How many axis are we allowed to know the spin for?

Answer 6

1 axis. Spin up or down

Question 7

State the rule for the number of states for spin

Answer 7

2s+1 = 2 (1/2) + 1 = 2

Question 8

What experiment was spin discovered in?

Answer 8

Stern-Gerlach experiment

Question 9

What was the classical prediction for the position of the atoms in the Stern Gerlach experiment?

Answer 9

A “splodge” of gold atms of the centre of the detector plane

Question 10

Why does the Stern Gerlach experiment’s classical prediction say there will be a splodge of gold atoms in the middle?

Answer 10

Because the atoms are unaffected by the magnetic field

Question 11

What was the result in the positions of the atoms in the Stern-Gerlach experiment?

Answer 11

They split into 2 distinct lines

Question 12

What does the splitting of the gold atoms into 2 distinct lines in the Stern Gerlach experiment tell us?

Answer 12

The Ag atoms have 2 discrete magnetic moment values along the direction of the external field

Question 13

How was the splitting of the gold atoms into 2 distinct lines in the Stern Gerlach experiment interpreted?

Answer 13

• The spin of the outer most electron of the Ag atom can take 2 values (opposite) along the line of the external field.
• The electron’s intrinsic magnetic moment causes the atomic beam to be spit into 2

Question 14

See page 5 of document for a diagram of the Stern Gerlach experiment

Answer 14

Look at it lol