Exploring Electron Configurations in Chemistry

Why do we care about electrons in chemical reactions?

• Because they are found in the nucleus

• Because they are involved in gaining, losing, and sharing during reactions

• Because they determine the atom's mass

• Because they are the heaviest part of the atom

How many electrons does a neutral hydrogen atom have?

• One

• None

• Three

• Two

What shape is the 1s orbital?

• Spherical

• Hourglass

• Square

• Triangular

In a ground state helium atom, how are the two electrons arranged in the 1s orbital?

• Both with the same spin

• Both with down spin

• Both with up spin

• One with up spin and one with down spin

What is the electron configuration for a helium atom at ground state?

• 1s1

• 1s2

• 2p2

• 2s2

Where does the third electron go in a lithium atom?

• 1s orbital

• 2s orbital

• 2p orbital

• 3s orbital

What is Hund's rule?

• Electrons in the same orbital must have opposite spins

• Electrons in the same subshell must have the same spin

• Electrons fill the lowest energy orbitals first

• Electrons fill empty orbitals in a subshell before pairing up

What is the electron configuration for a carbon atom?

• 1s2 2s2 2p2

• 1s2 2s2 2p1

• 1s2 2s1 2p3

• 1s2 2s2 2p3

How many electrons does a nitrogen atom have in its 2p orbitals?

• Four

• Two

• One

• Three

What are the two ways to represent electron configurations?

• Orbital shapes and molecular shapes

• Energy level diagrams and molecular diagrams

• Molecular diagrams and electron configurations

• Energy orbital diagrams and electron configurations