Valence Electrons and charges… Ag +1 Cd 2+ Zn +2
Ionic Compounds Between a metal (cation) and a nonmetal (anion) The goal is to make the electrons lost equal the electrons gained (making the overall charge = to zero) To write the formula, you must criss cross the ions charges and make them subscripts Al +3 O -2
Compound nameIonsCriss Cross!! Final Formula calcium chloride aluminum oxide lithium fluoride magnesium phosphide **Criss cross charges to make subscripts, make sure subscripts are in the lowest whole number ratio
FormulaCompound name CaCl 2 Al 2 O 3 Na 2 O BaI 2 **Name the cation first, then name the anion adding –ide to the ending
Ionic Compounds with transition metals -Remember that transition metals can have different numbers of valence electrons and charges, so we have to indicate the charge the metal takes with a roman numeral in the name -Criss cross the charges to make subscripts and make sure they are the lowest whole number ratio Compound name IonsCriss Cross!Final Formula Iron (III) oxide Tin (IV) chloride Lead (IV) oxide Tin (II) sulfide
Formula Non-Metal Ion with Charge Find Charge of Metal Name PbCl 2 Cu 2 S SnO CoF 3 When writing the name, you must put a roman numeral to indicate the charge of the metal. You have to “uncriss-cross” to find the charge of the metal, the charge of the nonmetal is always constant
Ionic Compounds with polyatomic ions You will still criss-cross the charge but polyatomic ions will be put into parentheses if there is more than one The overall charge must still equal zero Compound name IonsCriss Cross! Final Formula Aluminum nitrate Ammonium phosphate Calcium hydroxide Copper (II) sulfate Zinc chlorate
Covalent Molecules - You will not worry about charges for covalent….no criss-cross - A covalent compound is composed of two different nonmetal elements. For example, a molecule of chlorine trifluoride, ClF3 contains 1 atom of chlorine and 3 atoms of fluorine. Step 1: Name the first non-metal using a prefix to indicate how many of that element was in the compound. Step 2: Name the second non-metal using a prefix and add the suffix -ide to the end of the name of the element. Number of atoms Prefix 1 2 3 4 5 6 7 8 9 10
FORMULANAME CO 2 N2O3N2O3 SO 3 NAMEPREFIXESFORMULA dinitrogen pentoxide chlorine monofluoride nitrogen trifluoride
Acids If anion ends in –IDEIf anion ends in –ATEIf anion ends in -ITE Hydro-stem-ic acid Stem-ic acid Stem-ous acid
FORMULAANION NAMEACID NAME HNO 3 (aq) HF (aq) H 3 PO 3 (aq) ACID NAMEANION NAME ANION FORMULA ACID FORMULA- Add H + to anion Nitrous acid Hydrobromic acid Acetic acid
Seven Diatomic Elements I 2, Br 2, Cl 2, F 2, O 2, N 2, H 2 You should know that the following elements exist as diatomic molecules when they are not bonded to another element. Remember the saying: I Bring Clay For Our New House Hydrogen H 2 Oxygen O 2 Nitrogen N 2 Fluorine F 2 Chlorine Cl 2 Bromine Br 2 Iodine I 2
Law of Conservation of Mass – total mass of products must equal total mass of reactants. Balance chemical equations by adjusting coefficients when necessary. Leave the subscripts(little numbers at the bottom) alone!!!! Coefficients are placed in front of compounds, never in the middle of a compound. Balancing Chemical Equations
Steps to Balancing Equations 1) Balance all metals first 2) Balance all polyatomic ions 3)Balance any remaining anions 4) If necessary balance Oxygens and Hydrogens
Balance the following equations: Example 1: 1 Zn + 2@ HCl → 1 ZnCl 2 + 1 H 2 Example 2: 1 Cu + 2 AgNO 3 → 1 Cu(NO 3 ) 2 + 2 Ag Example 3: 1 Al 2 (SO 4 ) 3 + 3 Ca(OH) 2 → Al(OH) 3 + 3 CaSO 4 Example 4: 1 Al 4 C 3 + __ H 2 O → 3 CH 4 + 4 Al(OH) 3
Writing Chemical Equations Reactants are written on the left side of a chemical equation. Products are written on the right side of a chemical equation. An arrow pointing to the right means “yields.” STEPS for writing chemical equations: 1.Write correct formulas for each of the reactants. Put a plus sign between the reactants to separate them. (A plus sign means “added to” or “reacts with.”) 2.Draw a yield arrow. 3.Write correct formulas for each of the products. Put a plus sign between the products to separate them. 4.Balance the equation.
Write and Balance the following equations: 1. A solid piece of Zinc reacts with Hydrochloric acid (HCl) to produce a solution of Zinc Chloride and Hydrogen gas as the products. 2. Sulfuric acid (H2SO4) is reacted with a solution of Sodium Hydroxide to produce a solution of Sodium Sulfate and water as the only products.
Practice Chlorine gas is bubbled through a solution of Lithium Iodide, and the products are found to be a solution of Lithium Chloride and solid Iodine.
Practice Solutions of Silver Nitrate and Barium Chloride are mixed, and the products are a precipitate of Silver Chloride and a solution of Barium Nitrate.