AP - Advanced Placement Atomic Structure and Periodicity 1

Question 1

Light of frequency 8.00 × 10¹⁴ Hz strikes a metal surface that has a work function of 2.50 × 10⁻¹⁹ J.
What is the maximum kinetic energy of the ejected photoelectrons? (h = 6.626 × 10⁻³⁴ J·s)

Accepted Answer

2.80 × 10⁻¹⁹ J

Answer

5.30 × 10⁻¹⁹ J

Answer

7.80 × 10⁻¹⁹ J

Answer

1.26 × 10⁻¹⁸ J

Question 2

Which of the following represents the correct ground-state electron configuration of chromium (Cr, Z = 24)?

Accepted Answer

[Ar] 3d⁵ 4s¹

Answer

[Ar] 3d⁴ 4s²

Answer

[Ar] 3d⁶ 4s⁰

Answer

[Ar] 3d³ 4s² 4p¹

Question 3

An electron's position is known with an uncertainty of 1.00 × 10⁻¹⁰ m. What is the minimum uncertainty in its momentum? (h = 6.626 × 10⁻³⁴ J·s)

Accepted Answer

5.27 × 10⁻²⁵ kg·m/s

Answer

1.05 × 10⁻²⁴ kg·m/s

Answer

2.11 × 10⁻²⁴ kg·m/s

Answer

6.63 × 10⁻²⁴ kg·m/s

Question 4

Using Slater's rules, what is the effective nuclear charge (Z_eff) experienced by a 3p electron in chlorine (Cl, Z = 17)?

Accepted Answer

6.10

Answer

7.00

Answer

5.75

Answer

12.85

Question 5

Which of the following elements has the most negative (largest magnitude) electron affinity?

Accepted Answer

Chlorine (Cl)

Answer

Fluorine (F)

Answer

Bromine (Br)

Answer

Oxygen (O)

Question 6

What is the de Broglie wavelength of an electron traveling at 2.00 × 10⁶ m/s? (mₑ = 9.109 × 10⁻³¹ kg, h = 6.626 × 10⁻³⁴ J·s)

Accepted Answer

3.64 × 10⁻¹⁰ m

Answer

7.27 × 10⁻¹⁰ m

Answer

1.82 × 10⁻¹⁰ m

Answer

3.64 × 10⁻⁷ m