Descriptive Abbreviations (s) Solid (l) Liquid (g) Gas (aq) Aqueous dissolved in water How do we know the states of matter in a reaction? Word problem tells us States of matter from the periodic table Common knowledge Episode 605

Determining State at Room Temperature All metals are solids except for mercury, which is a liquid. Most non-metals are gases with these exceptions: Liquid – bromine Solids – carbon, phosphorus, sulfur, selenium, tellurium, and astatine All metalloids are solids Ionic compounds are solid, unless told otherwise. Covalent compounds are liquid, unless told otherwise. Episode 605

When heated, solid mercury (II) oxide yields mercury and oxygen gas. Write the balanced chemical equation including the descriptive abbreviations for the state of matter. 2 HgO(s) → 2 Hg(l) + O2(g) Episode 605

Classifying Reactions http://video.about.com/chemistry/What-Are-Types-of-Chemical-Reactions.htm Synthesis Two or more substances combine to form a more complex substance A + B  AB Fe(s) + S(s)  FeS(s) H20(l) + SO3(g)  H2SO4(aq) (acid rain) http://www.natgeoeducationvideo.com/film/1233/acid-rain Episode 605

Classifying Reactions Decomposition A single substance is broken down into two or more simpler substances AB  A + B H2O (l)  H2(g) + O2(g) 2HgO  2Hg(l) + O2↑ Episode 605

Classifying Reactions Single Replacement A free element replaces a less reactive element in a compound A + BY  AY + B Zn (s) + 2HCl(aq)  ZnCl2(aq) + H2(g) 2Al(s) + 3CuCl2(aq)  2AlCl3(aq) + 3Cu(s) Cu(s) + MgCl2(aq)  Activity Series: an arrangement of elements in the order of their tendency to react NR (no reaction) Episode 605

Activity Series Decreasing activity Lithium Potassium Barium Calcium Sodium Magnesium Aluminum Manganese Zinc Chromium Nickel Tin Lead (Hydrogen) Copper Mercury Silver Gold Decreasing activity Episode 605

Classifying Reactions Double Replacement The elements of a reacting compounds replace each other Normally takes place in an aqueous solution Also called metathesis reaction AX + BY  AY + BX 2KI(aq) + Pb(NO3)2(aq)  PBI2(s) + KNO3(g) Precipitate An insoluble solid May be represented in an equation by (s) or ↓ NaCl(aq) + AgNO3(aq)  NaNO3(aq) + AgCl ↓ Episode 605

Classifying Reactions Combustion Involves the reaction of a substance with oxygen Often called burning The complete combustion of a hydrocarbon produces CO2 and H2O CxHy + O2  CO2 + H20 C3H8(g) + 5O2(g)  3CO2(g) + 4H2O(l) CH4(g) + 2O2(g)  CO2(g) + 2H2O(l) Episode 605