Unit 3 Flashcard: Atomic Structure

Front

In an atom, when the atomic number equals the number of electrons, the atom is said to be ______.

Back

neutral

Front

Who discovered the proton?

Back

Goldstein

Front

Which scientist saw that particles in a gas were attracted to the positive plate of the cathode ray?

Back

Thomson

Front

An atom or group of atoms with a positive or negative charge is called a(n) ______.

Back

ion

Front

Who was the first scientist to think about atoms?

Back

Democritus

Front

What is the smallest unit of an element that retains the properties of that element?

Back

atom

Front

What is the center of an atom called?

Back

nucleus

Front

What are the negatively charged particles in an atom called?

Back

electrons

Front

What is the term for atoms of the same element that have different numbers of neutrons?

Back

isotopes

Front

What is the charge of a proton?

Back

positive