February 20, H Chem Nomenclature All Notes 9.25.notebook THOSE LOOK FAMILIAR

Transcription

1 Warm Up: Write from memory the definions of: Valence e Caon Anion Octet Rule Isotope THOSE LOOK FAMILIAR Law of Definite Proporons Rao of atoms in a cmpd equates to the rao of masses of each element (masses of elements are always in same proporons) Law of Mulple Proporons = Dalton! Mulple proporons are possible of the same 2 elements (water 2:1 and peroxide 2:2) Nomenclature (naming compounds and wring formulas) In Chemistry there are: Symbols (for elements ; we call them atoms) ex. Na or Cl Formulas (for compounds; we call them molecules or formula units) Ex. NaCl or CO 2 Equaons (for reacons) Ex. 2Na(l) + Cl 2(g) 2NaCl(s) Characteristics: There are two types of compounds/bonding: Ionic (start with a metal or a posive polyatomic ion); M&NM Called formula units Have high melng points (why? Ions have stronger bonds) Are electrolyc in their molten (liquid) or aqueous state (soln) Are RT Have a crystalline structure (think salt ), usually brile. Usually soluble in water (will dissolve!) DONATE e in order to bond, which makes caons and anions! Covalent (start with a nonmetal); NM & NM Called molecules (bc NO IONS!) Low melng points (think buer weaker bonds) Volale (tendency to vaporize) Non electrolyc Share e in bonding in order to have both octet (8ve ) Compound Formulas Ex. SO 3 Tells us: types of element in the compound How many atoms of each The way the compound is bonded and therefore its properes Tells us if it's a molecular or ionic cmpd definions? Which of the following compounds are: electrolyc? Which are volale? Probably soluble? Na 2 S SCl 4 Al 2 O 3 KF F 2 OF 2 1

2 Pull out Polyatomic Ions Sheet Start to memorize these! Always use parentheses, please! Make polyatomic ion flash cards? ate = 1 more O ate another O ite = 1 less O hypo = 2 less O ium = ammonium, hydronium ide ion = hydroxide ion, cyanide ion Wring compound formulas: Ionic: (1) get the symbol & charge of the ion f rom: > PToE > Monatomic ions table (pg 192) > Or polyatomic ion sheet How to get charges from the periodic table: All atoms want to have 8 ve = very stable! Count to the nearest noble gas (skip T metals) Does the atom have to gain or lose e to get to that noble gas? (2) Criss cross charges (making the atom electrically neutral) Zinc = Zn = +2 Silver= Ag = + 1 Tin = Sn = +2 or +4 Cobalt = Co = +2 Iron = Fe = +2, +3 Cadmium = Cd = +2 Transion Metals variability in charges (Cu, Fe, Hg, Pb, Sn, Cr, Mn, Co) Stock System: Roman numerals aer name (tells you charge!) Classical System: Root word, ous (caon smaller of the two possible ionic charges) or ic (caon larger of the two possible) unsure of charge though 2

3 Pracce just ionic cmpd names Covalent: Make subscripts out of prefixes from the name > Mono 1 > Di 2 > Tri 3 > Tetra 4 > Penta 5 > Hexa 6 > Hepta 7 > Octa 8 Feb 20 8:08 AM Pracce just with molecular cmpds Naming Compounds Ionic: > Name the ions Polyatomic ions «do not change name Monatomic caons «Do not change name» Ex. Mg = magnesium Mg 2+ = magnesium If transion metals «Include the charge of the ion in parentheses (you will have to calculate the charge)» Ex. SnCl 2 n(ii) Ionic cont Monatomic anions > Drop the last syllable (or two) and add the suffix ide» Ex. Cl = chlorine Cl = chloride F = fluorine F = fluoride Covalent Wring the Names: Add prefixes to names of elements to indicate the number of atoms present. End the second element in ide. If there is only one atom of the first element, do not put a prefix > Mono 1 > Di 2 > Tri 3 > Tetra 4 > Penta 5 > Hexa 6 > Hepta 7 > Octa 8 Ex. ClO 7 N 3 F 2 3

4 Flow Chart Contains prefixes molecular cmpd use prefixes to write formula! No prefixes ionic cmpd use criss cross to write formula! Oct 10 8:16 AM Oct 10 8:18 AM Oct 10 8:18 AM Oct 10 8:19 AM Oct 10 8:20 AM 4

5 Oct 10 8:33 AM Oct 10 8:34 AM BI/ BM/ T Formula sulfur trioxide Iron (III) carbonate barium bromide tin (II) fluoride magnesium oxide Oct 10 8:34 AM BI/ BM/ T BI/ BM/ T Formula Formula chlorine monoxide sulfur hexafluoride silicon tetrachloride Aluminum acetate diphosphorus sulfide chlorine trifluoride potassium nitrite beryllium oxide ammonium chloride magnesium fluoride 5

6 Diatomic molecules "H plus 7" Pracce on your own! H 2 O 2 N 2 F 2 Cl 2 Br 2 I 2 At 2 (we never use...) Who am I? Ca(NO3)2 ALWAYS PUT PARENTHESES ON POLYATOMIC IONS! Acid Nomenclature Rules pg 272 H + + CO3 2 H2CO3 Acid Nomenclature Acids are compound that have an acidic hydrogen ion (H in front) Naming acids: (1) Binary Acids (HNm) To name use form: Hydro ic acid (2) Ternary acids (HXO) No "hydro" If polyatomic ion ends in ate, drop ate and add If poyatomic ion ends in ite, drop ite and add ic acid ous acid Examples: HCl H 2 S HClO 2 HNO 3 HCN H 2 CO 3 You Try: HF H 3 N HNO 2 H 2 Cr 2 O 7 H 2 C 2 O 4 6

7 Wring formulas for acids Treat like it is ionic > If it starts with "hydro" it is bonded to a NM from the PToE > If no "hydro" bonded to a polyatomic ion Ex. Chromic acid Acec acid You try: Hydrophosphoric acid Phosphoric acid Hypochlorous acid Sulfurous acid Sulfuric acid Hydrosulfuric acid Perchloric acid Organic Nomenclature Prefixes: # of Carbons Functional Group Suffix Meth 1 Eth 2 Alkanes 2n + 2 ane Structure of Functional Group C H and C C bonds Examples: Propane Pentane Prop 3 Alkenes (2n for one db ene But 4 bond) Butane Pent 5 Hex 6 Alkynes (2n 2) yne 2, butene hept 7 oct 8 Alcohols ol Butanol You try: Hexane Ethanol Octane Propyne Pentanol pentene Feb 20 5:35 PM 7