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2: Atoms, Molecules, and Ions

  • Page ID
    428678
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    This chapter will describe some of the fundamental chemical principles related to the composition of matter, including those central to the concept of molecular identity.

    • 2.1: Atomic Theory
      This chapter will describe some of the fundamental chemical principles related to the composition of matter, including those central to the concept of molecular identity.
    • 2.2: Atomic Structure, Isotopes, and Atomic Mass
      An atom consists of a small, positively charged nucleus surrounded by electrons. The nucleus contains protons and neutrons; its diameter is about 100,000 times smaller than that of the atom. The mass of one atom is usually expressed in atomic mass units (amu), which is referred to as the atomic mass. An amu is defined as exactly \(1/12\) of the mass of a carbon-12 atom and is equal to 1.6605 \(\times\) 10−24 g.
    • 2.3: Chemical Formulas
      A molecular formula uses chemical symbols and subscripts to indicate the exact numbers of different atoms in a molecule or compound. An empirical formula gives the simplest, whole-number ratio of atoms in a compound. A structural formula indicates the bonding arrangement of the atoms in the molecule. Ball-and-stick and space-filling models show the geometric arrangement of atoms in a molecule. Isomers are compounds with the same molecular formula but different arrangements of atoms.
    • 2.E: Atoms, Molecules, and Ions- Homework
      End of chapter homework problems for Chapter \(\PageIndex{1}\).

    Contributors and Attributions

    Thumbnail: Spinning Buckminsterfullerene (\(\ce{C60}\)). (CC BY-SA 3.0; unported; Sponk).


    This page titled 2: Atoms, Molecules, and Ions is shared under a CC BY license and was authored, remixed, and/or curated by Scott Van Bramer.