Unit 2 Test REVIEW

Front

What happens to an electron when it moves from a lower energy level to a higher energy level?

Back

The electron becomes more excited.

Front

What is the hyphen notation for an atom of calcium with 20 protons, 20 electrons, and 22 neutrons?

Back

calcium - 42

Front

What is the electron configuration for Chlorine (Cl)?

Back

1s² 2s² 2p⁶ 3s² 3p⁵

Front

In a chemical compound, how do you determine the number of different elements present?

Back

Count the unique types of atoms in the compound.

Front

What are valence electrons?

Back

Electrons in the outermost energy level of an atom.

Front

What is the significance of valence electrons in chemical bonding?

Back

Valence electrons determine how an atom can bond with other atoms.

Front

How do you calculate the mass number of an atom?

Back

Add the number of protons and neutrons in the nucleus.

Front

What is the difference between an atom and an ion?

Back

An atom is neutral, while an ion has a net charge due to the loss or gain of electrons.

Front

What is the role of neutrons in an atom?

Back

Neutrons contribute to the mass of the atom and stabilize the nucleus.

Front

How does the electron configuration relate to the position of an element in the periodic table?

Back

The electron configuration determines the element's group and period.