Skip to main content
2: Topics in General Chemistry II
-
-
Last updated
-
-
Save as PDF
-
-
-
2.1: The Structure of Atoms
-
Atoms are composed of three main subatomic particles: protons, neutrons, and electrons. Protons and neutrons are grouped together in the nucleus of an atom, while electrons orbit about the nucleus.
-
-
2.2: The Elements
-
All matter is composed of elements. Chemical elements are represented by a one- or two-letter symbol.
-
-
2.3: Atomic Number and Mass Number
-
Elements can be identified by their atomic number and mass number. Isotopes are atoms of the same element that have different mass number.
-
-
2.4: Atomic Weight
-
Atoms have a mass that is based largely on the number of protons and neutrons in their nucleus.
-
-
2.5: The Periodic Table
-
The chemical elements are arranged in a chart called the periodic table. Some characteristics of the elements are related to their position on the periodic table.
-
-
2.6: Valence Electrons and Electron Dot Formula
-
The number of valence electrons for a main group element is the same as the group number of the element. This information is represented as electron dot structure.
-
-
2.7: The Mole and Mole-Mass Conversions
-
Chemists use the term mole to represent a large number of atoms or molecules just as a dozen implies 12 things. Since the mole is a very large number, we use mass to keep track rather than by counting individual atoms.
-
-
2.8: Physical and Chemical Properties and Changes
-
A physical property is a characteristic of a substance that can be observed or measured without changing the identity of the substance. A chemical property describes the ability of a substance to undergo a change to form new substances.
-
-
2.9: End of Chapter Problems
-
This problem set is based on Chapter 2 topics.