1­Acids Bases Salts and Electrolytes 2017.notebook
January 23, 2017
Unit 12: Acids & Bases
Aim: What are the definitions and properties of an acid and a base?
Mar 23­12:08 PM
Properties of an Acid
5.
3.
Are electrolytes. (Dissociate and conduct electricity 2.
when aq)
Taste Sour
7.
Reacts with
a metal to form H2(g)
Turns Litmus Red
6.
4.
Neutralizes a base to produce a salt and H­2O
Caustic and Corrosive
1.
pH is less than 7
Click and reveal 3
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1­Acids Bases Salts and Electrolytes 2017.notebook
January 23, 2017
Jan 23­12:38 PM
Properties of an Acid
Acids will react with most metals to yield hydrogen gas through a single replacement reaction.
Table J will tell you if
with an acid.
Mar 23­1:31 PM
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1­Acids Bases Salts and Electrolytes 2017.notebook
January 23, 2017
Properties of an Acid
Acids usually have an "H" in the beginning of the formula except for acetic acid, CH3COOH.
Mar 23­1:31 PM
Properties of a Base
1.
Are electrolytes. Dissociate and conduct 4.
electricity when (aq)
5.
Tastes Bitter
Turns Litmus Blue
7.
Slippery
6.
2.
Neutralizes an acid to produce a salt and H2O
Caustic
3.
pH is greater than 7
Click and reveal 3
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1­Acids Bases Salts and Electrolytes 2017.notebook
January 23, 2017
Jan 23­12:39 PM
Properties of a Base
Bases will have a metal with an OH­ ion attached EXCEPT for ammonia, NH3.
BEWARE of the Imposters!
CH3OH
NaOH Mar 23­1:50 PM
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1­Acids Bases Salts and Electrolytes 2017.notebook
January 23, 2017
Properties of a Salt
1) Ionic­ made up of a metal and a nonmetal OR polyatomic ions.
2) pH= 7, neutral.
3) All salts are electrolytes because they dissociate into ions.
• All salt solutions contain mobile ions and conduct.
• Also conduct when molten because ions become mobile.
4) Salts will form during neutralization reactions between an acid and a base.
Mar 23­2:10 PM
Acid and Base Theories and Electrolytes
Aim: What are the differences between the Arrhenius and Alternate (Bronsted) acid­base theories?
Mar 23­12:08 PM
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1­Acids Bases Salts and Electrolytes 2017.notebook
January 23, 2017
Dissolving vs. Dissociation
https://www.youtube.com/watch?v=0cPFx0wFuVs
Mar 25­9:01 PM
Electrolytes
Electrolyte ­ a substance that when aqueous dissociates and conducts electricity due to the presence of mobile ions.
ACIDS, BASES and SALTS are electrolytes.
The stronger the acid (most protonation of H+ ions), the better it conducts electricity.
• Table K gives some of the strongest and best conducting acids.
Mar 23­1:54 PM
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1­Acids Bases Salts and Electrolytes 2017.notebook
January 23, 2017
Non­Electrolytes
If a compound does not produce ions in solution it is a nonelectrolyte.
Covalent compounds, molecular solids, are nonelectrolytes and do not break up into ions solution.
Examples: C6H12O6 and CH3OH
DO NOT DISSOCIATE BECAUSE THERE ARE NO IONS PRESENT.
Mar 23­2:35 PM
Arrhenius Definition of an Acid
Arrhenius Acids ­ a substance that yields hydronium ions, H3O+ ions, as the only cation in solution.
a) HCl + H2O → Mar 23­1:31 PM
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1­Acids Bases Salts and Electrolytes 2017.notebook
January 23, 2017
Arrhenius Definition of a Base
Arrhenius Base ­ a substance that yields hydroxide ions, OH­ ions as the only anion in solution
NaOH → Mg(OH)2 → Mar 23­1:50 PM
A. Mg(OH)2 + H2O → Mg+2 + 2 OH­
B. H2CO3 + H2O → H3O+ + HCO3­
1) Which equation represents the dissociation of an Arrhenius acid?
2) Which equation represents the dissociation of an Arrhenius base?
May 3­10:03 AM
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1­Acids Bases Salts and Electrolytes 2017.notebook
January 23, 2017
Alternate Definition of an Acid
Bronsted acid: A substance that donates a proton (H+) to another substance. "Proton DONOR".
NH3 + H2O ↔ NH4+ + OH­
Bronsted base: A substance that accepts a proton (H+) from another substance. "Proton ACCEPTOR."
Mar 24­10:23 AM
Alternate Definition of a Base
Bronsted base: A substance that accepts a proton (H+) from another substance. Proton ACCEPTOR.
NH3 + H2O ↔ NH4+ + OH­
Mar 24­10:23 AM
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1­Acids Bases Salts and Electrolytes 2017.notebook
January 23, 2017
Identify the Alternate (Bronsted) Acid and Base in each reaction:
1) H2CO3 + H2O → HCO3­ + H3O+
2) HSO4­ + H2O → H2SO4 + OH­­
Mar 24­12:23 PM
Practice Questions
1) Which species is classified as a Bronsted acid?
A) CH3OH
B) NaCl
C) LiOH
D) H2SO4
2) Which of the following substances will turn red litmus paper blue?
A) CH3OH
B) NaCl
C) LiOH
D) H2SO4
3) The compound NaOH can be described as an:
A) arrhenius base and an electrolyte C) arrhenius acid and a nonelectrolyte
B) arrhenius acid and an electrolyte D) arrhenius base and a nonelectrolyte
4) Which species donates H3O+ ions as the only positive ion in solution?
A) HCl
B) Mg(OH)2
C) CH4
D) BaF2
5) Given the reaction:
NH3 + HCl → NH4Cl
In this reaction, ammonia molecules (NH3) act as a base because they
A) donate hydroxide ions (OH­)
C) accept hydrogen ions (H+)
D) donate hydrogen ions (H+)
B) accept hydroxide ions (OH­)
Mar 24­12:23 PM
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