Unit 3: Atomic Structure Test Review

Joseph Priestly invented ____________ and ____________ water, leading to the invention of soda.

Nitrous oxide and carbonate.

____________ discovered the role oxygen plays in combustion and recognized and named oxygen and hydrogen.

Antoine Lavoisier.

Atoms or a group of atoms with a positive or negative charge are called ____________.

Ions.

The mass of a single atom is measured in ____________.

Atomic Mass.

Ions are formed when ____________ are lost.

Electrons.

Opposite charges ____________ each other, like charges ____________ each other.

Attract; repel.

An atom is ____________ when the number of protons equals the number of electrons.

Neutral.

__________ are formed when electrons are gained.

Anions.

The scientist who measured the exact charge and mass of an electron is ____________.

Robert Millikan.

The scientist who discovered the electron is ____________.

J.J. Thompson.

The atomic mass is the average of the elements' ____________.

Isotopes.

The group of elements that tend to gain electrons is called ____________.

Nonmetals.

The scientist who gave the atom its name is ____________.

Democritus.

____________ said that all matter is comprised of indivisible particles called atoms and provided evidence to back it up.

John Dalton.

The first person who thought about atoms is ____________.

Democritus.

Electrons that are lost create a ____________.

Cation.

The scientist who discovered the neutron is ____________.

Sir James Chadwick.

The scientist who used the Gold Foil experiment to discover the nucleus is ____________.

Ernest Rutherford.

The scientist who discovered the proton is ____________.

Eugen Goldstein.

Electrons are arranged in ____________ around the nucleus.

An electron cloud.

____________ believed everything was composed of four elements: earth, air, fire, and water.

Aristotle.

The four major points of Dalton’s atomic theory are: 1) All elements are composed of indivisible particles called atoms. 2) ____________ 3) ____________ 4) ____________

Atoms of the same element are identical; Atoms of different elements mix or combine in whole number ratios; Chemical reactions occur when atoms separate, join, or rearrange.

An element has 3 common isotopes with specific masses and occurrence percentages. The average atomic mass of this element is ____________ amu.

20.18.

An element has a common average atomic mass of 39.948 amu. The % abundance of the second isotope is ____________, and the mass of the second isotope is ____________ amu.

66.35%; 41.97.