8th Chapter 9 Understanding the Atom

Which of the following determined that cathode rays are negatively charged?

• Aristotle

• Dalton

• Rutherford

• Thomson

Which of the following found that atoms have a nucleus?

• Aristotle

• Dalton

• Rutherford

• Thomson

The three basic components of an atom are _____.

• protons, neutrons, and ions

• protons, neutrons, and electrons

• protons, neutrinos, and ions

• protium, deuterium, and tritium

The nucleus of an atom consists of _____.

• protons, neutrons, and electrons

• protons and neutrons

• electrons

• neutrons

A single proton has which electrical charge?

• positive charge

• no charge

• negative charge

• either a positive or a negative charge

Which two particles would be attracted to each other?

• electrons and neutrons

• electrons and protons

• protons and neutrons

• All particles are attracted to each other.

The energy levels of an atom are occupied by ____.

• electrons

• protons

• neutrons

• ions

_____ does not change an element into another element.

• Alpha decay

• Beta decay

• Gamma decay

• Omega decay

In _____, the atomic number decreases by two.

• alpha decay

• beta decay

• gamma decay

• omega decay

Henri Becquerel accidentally discovered radiation while working with minerals containing _____.

• polonium

• radium

• sodium

• uranium