CHEM 1100 Chapter Notes - Chapter 4: Hexa, Molar Mass, Unified Atomic Mass Unit

• School: University of Guelph
• Department: Chemistry
• Course: CHEM 1100
• Professor: Kim Bolton

Document Summary

Reactions: molecules determine the behaviour of matter. Chemical compounds and chemical formulas: all matter is composed of atoms, atoms are usually bound together to form compounds. Chemical formulas: represent a compound with a chemical formula which indicates the elements present in the compound and the relative number of atoms of each, ex. The chemical formula for table salt is nacl and is composed of sodium and chlorine atoms in 1:1 ratio: ex. Ca(no3)2 has 1 ca, 2 n, 6 o. Ionic and molecular compounds: only few elements exist as isolated atoms with stable electron configurations (noble gases, elements with unstable electron configurations will usually form compounds with other elements to gain stability. Ionic bond when a metal and non-metal bond together a metal transfers some or all of its valence electrons to the non-metal, and both become stable: ex. In sodium chloride sodium atoms lose an electron to form na+ and chlorine gain an electron to form.