CHY 102 Lecture Notes - Lecture 13: Oxidation State, Significant Figures, Sodium Hydroxide

• School: Ryerson University
• Department: Chemistry
• Course: CHY 102
• Professor: Derrick Heyd

Document Summary

After neutralisation, solutions are not as acidic or basic as reagents e. g. naoh (aq) + hcl (aq) nacl (aq) + h2o (l) base acid salt water. Na+ + oh- + h+ + cl- na+ + cl- + h2o (l) Note: (aq) is implied for all ions. H+ (aq) + oh- (aq) h2o (l) Mol: mg(oh)2 (s) + 2 hcl (aq) mgcl2 (aq) + 2 h2o (l) Ci: mg(oh)2(s) + 2 h+ + 2 cl- mg2++ 2 cl- + 2 h2o (l) net: mg(oh)2 (s) + 2 h+ (aq) mg2+ (aq) + 2 h2o (l) Consider the possibility of a gas being formed: Mol: 2 hcl (aq) + na2s (aq) h2s (g) + 2 nacl (aq) Ci: 2 h+ + 2 cl- + 2 na+ + s2- h2s (g) + 2 na+ + 2 cl- net: 2 h+ (aq) + s2- (aq) h2s (g) Ph expresses [h+] on a log scale: ph = -log([h+]) {or [h+] = 10-ph}