Chem

• Law of Definite Proportions: the number of atoms of the elements always exist in the same ratio is consistent with these observations
• Law of Multiple Proportions: 2 elements react to form more than 1 compound
• Alpha Particles: 2 protons and 2 neutrons
• Isotopes: atoms of the same element that differ in mass
• Electrons: outside of nucleus, -1.602 x 10^-19 charge, 1- unit charge, 0.00055 mass (amu), and 0.00091 x 10^-24 mass (g)
• Protons: nucleus, 1.602 x 10^-19 charge, 1+ unit charge, 1.00727 mass (amu), and 1.67262 x 10^-24 mass (g)
• Neutrons: nucleus, 0 charge, 0 unit charge, 1.00866 mass (amu), and 1.67493 x 10^-24 mass (g)
• Atomic Number (z) = Number of Protons
• Mass Number (A)= Number of Protons plus Number of Neutrons
• A - z = Number of Neutrons
• Ion= numbers of subatomic particles are not equal, the atom is electrically charged
• Atomic Charge: Number of Protons - Number of Electrons
• Anion: an atom that gains 1 or more electrons and will have a negative charge
• Cations: positively charged atoms formed when an atom loses 1 or more electrons
• Isotopes: any element written by placing the mass number as a superscript to the left of the element symbol
• Atomic Mass of a single atom is around equal to it's mass number
• Avg Mass= (fractional force x isotopic mass)i
• Molecular Formula: representation of molecules that uses chemical symbols to indicate types of atoms followed by subscripts to show the number of atoms of each type in the molecule
• Structural Formula: same as molecular formula but also shows how atoms are connected in the molecule
• Empirical Formula: types of atoms that are present and the simplest whole number ratio of the number of atoms in the compound
• Isomers: compounds with same chemical formula but different molecular structures
• Spatial Isomers: atoms in space can be different