Exam 1 Review

Conversions

100

How many atoms are present in 2.00 mol of Carbon?

1.20 x 10²⁴ atoms

200

What is the molar mass of Al₂(CO₃)₃?

233.99 g/mol

300

An element has three stable isotopes with masses of 62.930 amu, 64.928 amu, and 65.926 amu. The two heavier isotopes have abundance of 27.5% and 4.2% respectively. What is the average atomic mass of the element?

63.605 amu 

400

An object has a density of 6.35 g/cm³. What is its density in kg/m³

6350 kg/m³

500

How many aluminum atoms are present in 5.0g of Al₂(CO₃)₃?

2.57 x 10²² Al atoms

Wavelength

100

If the wavelength of electromagnetic radiation increases, what happens to its frequency?

Frequency decreases

200

Approximately what wavelength range is visible light?

400 to 700 nm

300

A barcode scanner emits lights with a frequency of 4.62 x 10¹⁴ s^-1. What is its wavelength?

6.49 x 10^-7 m or 649 nm 

400

What is the frequency of light with a wavelength of 532 nm? 

5.64 x 10¹⁴ Hz

500

What is the energy of one photon with a wavelength of 640 nm?

3.11 x 10^-19 J

Electron Configuration

100

Write the full electron configuration for Ne.

1s²2s²2p⁶

200

Write the noble-gas electron configuration for Ca.

[Ar]4s²

300

Write the noble-gas electron configuration for Fe.

[Ar]4s²3d⁶

400

Sulfur has the configuration 1s²2s²2p⁶3s²3p⁴. How many unpaired electrons does it have?

2 unpaired

500

Give the electron configuration of Fe³⁺ and state whether it is paramagnetic or diamagnetic.

[Ar]3d⁵ ; Paramagnetic

Quantum Numbers

100

What are the two allowed values of the spin quantum number, m_s.

+1/2 and -1/2

200

Match the angular momentum quantum number l with the subshells s,p,d, and f.

s=0, p=1, d=2, f=3

300

For 3d subshell, give n, l, and all possible m_l values? 

n=3, l=2, m_l= -2, -1, 0, +1, +2

400

Why does 3f subshell not exist?

For n=3, l can only be 0, 1, or 2 because l values run from 0 to n-1. 

500

if n=4 and l=3, how many orbitals are in that subshell and what is the maximum number of electrons it can hold?

7 orbitals; 14 electrons 

Periodic Trends

100

What are rows and columns of the periodic table called?

rows = periods

columns = groups/families

200

What happens to atomic radius as you move down a group and left to right across a period?

radius increases down a group and decreases across a period

300

Compared with its neutral atom, is a cation generally larger or smaller? What about anion?

Cation is smaller, anion is larger 

400

What happens to effective nuclear charge, Zeff, from left to right across a period and what does that do to atomic size?

Zeff increases causing atomic size to decrease

500

Na⁺, Mg²⁺, and Al³⁺ each have 10 electrons. Rank them from largest radius to smallest radius.

Na⁺ > Mg²⁺ > Al³⁺