Chemistry Review

Periodic Table ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● Pure Substances Atomic Number - # of protons (and electrons) in the nucleus of the atom Atomic Mass - mass of the nucleus Period - horizontal rows (# of energy levels) Group - vertical columns (elements with similar properties) -Same # of valence electrons = behave similarly (elements) Representative elements - Groups 1,2 and 13-18 Transition metals - Groups 3-12 Alkali metals - Group 1 Alkaline earth metals - Group 2 Halogens - Group 17 Noble Gases - Group 18 (stable) Metals -solid, lustre, malleable, good conductors Non-metals -liquid or gasses, no lustre, non-malleable, bad conductors Proton - positive, p+, nucleus, atomic # Electrons - negative, e-, orbits (outside nucleus), atomic # Neutron - neutral (Ø), nØ, rounded atomic mass - atomic # Ions and Bohr Rutherford Diagram ● Unstable - outer orbit/valence shell doesn't have max # of electrons (not full) -Form ions by losing or gaining electrons (full outer orbit) ● Cation - Losing electrons = positively charged ● Anion - Gaining electrons = negatively charged -Ending of name changes to “ide” INSERT BOHR RUTHERFORD DIAGRAM Chemical Compounds Ionic Compounds ● Metal and non-metal (metal transfers electron to non-metal) ● Hard, brittle, high melting points ● Resulting cation and anion form an ionic bond ● Name of metal followed by non-metal ending in “ide” ● Names may have roman numerals if metal is a transition metal with more than one possible charge ● Use criss cross rule (lowest term charges) Ionic Compounds with Polyatomic Ions ● Cation and anion (at least one polyatomic ion) ● Use criss cross rule (use brackets for polyatomic ion if need subscript) ● Name of metal (or ammonium) then polyatomic ion Molecular Compounds ● Non-metals only (sharing of electrons = covalent bond between atoms) ● ● ● ● ● ● ● ● ● ● ● Diatomic molecules (HOFBrINCl) Translate prefixes into subscripts (DON’T put into lowest terms) Translate subscripts into prefixes Second name = ide 1 = mono, 2 = di, 3 = tri, 4 = tetra, 5 = penta, 6 = hexa, 7 = hepta, 8 = octa, 9 = nona, 10 = deca If two vowels are beside each other and sound the same, drop one (monooxide = monoxide) Chemical Reactions Word equation - Names of chemicals written in words (full) Chemical equations - Chemical formulas used Products - New substances Reactants - Starting substances Aqueous - Dissolved in water How to Count Atoms 1. Symbol of element = one atoms of that element Ca = 1 calcium atom 2. Subscript = number of atoms N² = 2 nitrogen atoms 3. Subscript outside bracket = all elements inside bracket multiplied 4. Coefficient = number written of a chemical symbol indicates # of atoms of that element -Can be written in front of a chemical formula -Indicated # of molecules of that compound -Multiplies # of atoms of each element in the formula Balancing Chemical Equations ● Uses coefficients to make # of each type of atoms in reactions = to atoms in products ● Represents Law of Conservation of Mass (In any given chemical reaction, the total mass of the reactants equals the total mass of the products) 1. Write word equation for reaction (if needed) 2. Write chemical skeleton equation for reaction 3. Count # of each type of atom in reactants and products 4. In skeleton equation multiply formula by appropriate coefficient until all atoms are balanced on both sides of arrow Types of Chemical Reactions Synthesis Reactions A + B → AB Two or more simple reactants combine to form a larger, more complex product Decomposition Reactions AB → A + B A large compound is broken down into two or more simpler products Single Displacement A + BC →Ac + B One element displaces/replaces an element in a compound Double Displacement AB + CD → AD + CB Two atoms in different compounds trade places. Reactants are often in aqueous solutions and one of the products will be insoluble and precipitate out a solution. Complete Combustion CxHx + O2→ CO2 + H2O A hydrocarbon fuel reacts quickly with oxygen in an environment where oxygen is plentiful. Hydrocarbon fuel burns completely to produce carbon dioxide gas and water vapour. Flame produced is hot, clean, and blue. Incomplete Combustion CxHx + O2 → CO2 + H2O + CO + C Hydrocarbon fuel reacts quickly with oxygen in an environment where there is a shortage of oxygen. Hydrocarbon fuel burns incompletely to produce carbon dioxide, water vapour, and poisonous carbon monoxide gas and solid carbon soot powder. Flame produced is cooler, orange, and flickering. Acids and Bases Binary Acids ● Only two elements (hydrogen + non-metal) ● Names begin with “hydro”; end with “ic acid” Oxy Acids ● Hydrogen + oxygen containing polyatomic ions ● Names don’t begin with “hydro”; start with stem of the polyatomic ion and end with “ic acid” Acids ● ● ● ● ● ● ● ● ● ● Conductor Stays/turns red with litmus paper Metal → fizzing Bromophenol blue → turns yellow Phenolphthalein → turns white Carbonate → fizzing Sour Molecular compounds Properties = result of hydrogen ion # of hydrogen ions depend on charge of anion part of compound Bases ● Begin with cation (usually metal); end with hydroxide (OH) or carbonate (CO3), or bicarbonate (HCO3) ● Conductor ● Stays/turns blue with litmus paper ● No reaction with metal ● ● ● ● ● ● ● Bromophenol blue →turn purple Phenolphthalein → turns bright magenta No reaction with carbonate Base = bitter, slippery Ionic Compounds Properties = result of hydroxide ions # of hydroxide ions depend on valence of metal ion PH Scale and Neutralization Reactions PH Scale Used to represent how acidic or basic a solution is ; logarithmic (a change of factor by 10) Neutralization Reactions -When an acid or base react to form neutral products -Products = usually ionic compound (a salt) + H2O -H+ ions and OH- ions react to form neutral H2O (HOH) -Double displacement reaction Acid + Base → Ionic Compound (salt) + Water Involve Carbonates (CO2 gas produced) (H2O + CO2)