Chapter 2

How many valence electrons do the alkaline earth metals possess?

2

How many valence electrons does an atom of Al possess?

3

List a possible set of four quantum numbers (n, ℓ, mℓ, ms) in order, for the highest energy electron in gallium, Ga. Refer to the periodic table as necessary.

4,1,0,1/2

How many valence electrons do the halogens possess?

7

How many orbitals are there in the third shell (n=3n=3)?

9

Rank the following elements in order of decreasing atomic radius: I, Cl, Br, F

I > Br > Cl > F

Which of the following arranges the given atoms in order of increasing atomic radius (shortest to longest)?

Kr, Se, Ca, and K

Rank the following elements in order of decreasing atomic radius: B, N, Li, Be

Li > Be > B > N

A certain element forms an ion with 10 electrons and a charge of +2. Identify the element.

Mg

No two electrons can have the same four quantum numbers is known as the

Pauli Exclusion Principle

Only two electrons, with opposing spins, are allowed in each orbital is known as the

Pauli Exclusion Principle

Give the ground state electron configuration for Sr.

[Kr]5s^2

Give the ground state electron configuration for Pb.

[Xe]6s^2 4f^14 5d^10 6p^2

Rubidium belongs to the ________ group of the periodic table.

alkali metal

Barium belongs to the ________ group of the periodic table.

alkaline earth metal

Identify an anion.

an atom that has gained an electron

Radon belongs to the ________ group of the periodic table.

noble gas

The shielding of electrons gives rise to an effective nuclear charge, Zeff, which explains why boron is larger than oxygen. Estimate the approximate Zeff felt by a valence electron of boron and oxygen, respectively?

+3 and +6

Which electron in sulfur is most shielded from nuclear charge?

An electron in a 3p orbital

The element that corresponds to the electron configuration 1s^2 2s^2 2p^6 3s^2 3p^6 4s^1 3d^5 is ________

Chromium

When filling degenerate orbitals, electrons fill them singly first, with parallel spins is known as

Hund's Rule

Which of the following elements is a metal?

Sn

Which element would most likely form an ion with a charge of -2?

Te

Place the following elements in order of decreasing atomic size: bismuth, bromine, neon, cesium, barium, and arsenic.

cesium > barium > bismuth > arsenic > bromine > neon