Gas Tests

cloudylimewater CO 2 popsburning splintH2H2 reignitesglowing splint O2O2 PositiveTestGas

Synthesis and Decomposition Reactions

Use Phase symbols (s) (l) (g) (aq) Polyatomic Elements: P 4 (s) and S 8 (s) Diatomic Elements: H 2 (g) N 2 (g) O 2 (g) F 2 (g) Cl 2 (g) Br 2 (l) I 2(s)

Ionic compounds are solid Li 3 N+ N 2 Li (s)(g) (s)  26 A + B  AB Elements combine to form compounds. Synthesis means to combine. + O 2 S8S8 8SO 2  (g)(s)(g) 8

electrolysis Decomposition means to break down. Compounds break down into elements which requires energy that comes from heating or electrolysis. Electrolysis uses inert electrodes and an electric current through a molten or aqueous solution. AB  A + B  HgOHg+ O 2(g)(l) 22 (s) H2OH2OH2H2 + O 2 22 (l) (g)  ∆ heat

N 2 (g) + 2 O 2 (g)  2 NO 2 (g) Molten table salt is electrolyzed to produce molten sodium and another gas. Nitrogen from the air reacts with oxygen to produce gaseous nitrogen dioxide. 2 NaCl (l)  2 Na (l) + Cl 2 (g) ∆

2 CuO (s)  2 Cu (s) + O 2 (g) A sample of Copper II oxide is heated. A silver spoon tarnishes when exposed to sulfur. 16 Ag (s) + S 8 (s)  8 Ag 2 S (s) Reaction Song