Ch 17 - The Atomic Nature of Matter

Terms & Objectives

The core ideas in this chapter include:

Matter is made of atoms.
Atoms are "eternal." They are not created or destroyed in chemical interactions.
Atoms are too small to be seen using visible light (approx. 10^-10m).
Molecules are made of atoms.
Atoms are made of protons, electrons & neutrons.
- Protons & neutrons reside in the nucleus. They are called "nucleons."
- The nucleus is extremely small compared to atom.
- Almost all of the mass of the atom is in the nucleus.
- Electrons "orbit" the nucleus.
- Electron mass is about 1/2000 proton or neutron mass.
The type of atom (element) is determined by the number of protons.
The number of neutrons determine the isotope.
Generally, number of electrons = number of protons.
- Fewer or greater number of electrons determine positive/negative ion.
Common phases of matter include solid, liquid, gas, plasma

When you complete Chapter 17, you should be able to:

... discuss the role of atoms as building blocks of matter.
... discuss the size of atoms, and evidence for the existence of atoms.
... discuss the concept "atoms are recyclable."
... identify elements as types of atoms, and know approximately how many elements exist.
... discuss, in general terms, the roles of protons, neutrons, and electrons in the atom.
... discuss the approximate relative masses of protons, neutrons, and electrons.
... discuss the relative size and mass of the atom and the nucleus.
... recognize that atoms combine to form molecules and compounds.
... tell what an ion is, in terms of the number of protons, neutrons, and electrons it contains.
... tell what an isotope is, in terms of the number of protons, neutrons, and electrons it contains.
... identify the four common phases of matter.

last update May 5, 2009 by JL Stanbrough