Learning Goal: To recognize acids, bases, and conjugate pairs. By the Arrhenius definition, an acid directly produces H+ ions in aqueous solution and a base directly produces OH? ions in aqueous solution. For example, HClproduces H+ and NaOH produces OH?: acid:base:HCl(aq)NaOH(aq)??H+(aq)+Cl?(aq)Na+(aq)+OH?(aq) To recognize Arrhenius acids, look for H at the beginning of the formula. To recognize Arrhenius bases, look for OH at the end of the formula. By the Brønsted-Lowry definition, an acid donates a H+ ion and a base accepts a H+ ion. For example, HCl donates a H+ ion to water and C5H5N accepts a proton from water. By showing water in the equation, we see a more complete picture of what is actually going on: acid:base:HCl(aq)+H2O(l)C5H5N(aq)+H2O(l)??H3O+(aq)+Cl?(aq)C5H5NH+(aq)+OH?(aq) To recognize Brønsted-Lowry acids, look for H at the beginning of the formula. To recognize Brønsted-Lowry bases, first make sure it\'s not an acid, and then look for N in the formula. Part A Classify each of these compounds as an Arrhenius acid, an Arrhenius base, or neither. HClO3 KNO3 Hg(OH)2 KOH Mn(OH)2 C3H8 HBr Ca(OH)2 HF H3PO4 Arhenius acid Arhenius base Neither Solution Arrhenius Acid : HClO3 , HBr , HF , H3PO4 Arrhenius base : Hg(OH)2 , KOH , Mn(OH)2 , Ca(OH)2 Neither : KNO3 , C3H8 .

1. Learning Goal:
To recognize acids, bases, and conjugate pairs.
By the Arrhenius definition, an acid directly produces H+ ions in aqueous solution and a base
directly produces OH? ions in aqueous solution. For example, HClproduces H+ and NaOH
produces OH?:
acid:base:HCl(aq)NaOH(aq)??H+(aq)+Cl?(aq)Na+(aq)+OH?(aq)
To recognize Arrhenius acids, look for H at the beginning of the formula. To recognize
Arrhenius bases, look for OH at the end of the formula.
By the Brønsted-Lowry definition, an acid donates a H+ ion and a base accepts a H+ ion. For
example, HCl donates a H+ ion to water and C5H5N accepts a proton from water. By showing
water in the equation, we see a more complete picture of what is actually going on:
acid:base:HCl(aq)+H2O(l)C5H5N(aq)+H2O(l)??H3O+(aq)+Cl?(aq)C5H5NH+(aq)+OH?(aq)
To recognize Brønsted-Lowry acids, look for H at the beginning of the formula. To recognize
Brønsted-Lowry bases, first make sure it's not an acid, and then look for N in the formula.
Part A
Classify each of these compounds as an Arrhenius acid, an Arrhenius base, or neither.
HClO3
KNO3
Hg(OH)2
KOH
Mn(OH)2
C3H8
HBr
Ca(OH)2
HF
H3PO4

2. Arhenius acid
Arhenius base
Neither
HClO3
KNO3
Hg(OH)2
KOH
Mn(OH)2
C3H8
HBr
Ca(OH)2
HF
H3PO4
Arhenius acid
Arhenius base
Neither
Solution
Arrhenius Acid : HClO3 , HBr , HF , H3PO4

3. Arrhenius base : Hg(OH)2 , KOH , Mn(OH)2 , Ca(OH)2
Neither : KNO3 , C3H8