Post on 27-Jun-2015
Launch: 1/19 Grab your binder and immediately take a seat!
Place launch paper on your desk.
Friday’s Quiz Data:
Today’s Objective: I can describe the properties of acids and bases.
90%
Launch: 1/19 Grab your binder and immediately take a seat!
Place launch paper on your desk.
Friday’s Quiz Data:
Today’s Objective: I can describe the properties of acids and bases.
82%
Launch: 1/19 Grab your binder and immediately take a seat!
Place launch paper on your desk.
Friday’s Quiz Data:
Today’s Objective: I can describe the properties of acids and bases.
80%
Launch: 1/19 Grab your binder and immediately take a seat!
Place launch paper on your desk.
Friday’s Quiz Data:
Today’s Objective: I can describe the properties of acids and bases.
87%
Announcements The semester ends tomorrow
Missing work is due today
Quiz tomorrow!
Lab due tomorrow!
Unit #6 exam moved to Thursday 1/28
January Calendar
What are acids & bases? – Part II
Mr. Heffner 1/21/10
Review: What are acids and bases? Solutions can be classified as…
Acids pH < 7 taste sour
Ex: lemon juice burn skin turn litmus paper red
Bases pH > 7 taste bitter
Ex: soap feel slippery turn litmus paper blue
“pH scale”
What are acids and bases? The Brønsted-Lowry definition:
Acids donate hydrogen ions Bases accept hydrogen ions
Hydrogen ions are positively-charged hydrogen atoms
Symbol =
charged atoms
H+
Example 1. In the following reaction, identify the acid and the
base.
HF loses (donates) = acid
H2O gains (accepts) = base
HF + H2O F- + H3O+ loses an
H+ forms gains an
H+ forms
Example 2. In the following reaction, identify the acid and the
base.
HSO4- gains (accepts) = base
H2O loses (donates) = acid
HSO4- + H2O H2SO4
- + OH-
gains an H+
forms loses an H+
forms
Example 3. In the following reaction, identify the acid and the
base.
HCl loses (donates) = acid
H2O gains (accepts) = base
HCl + H2O Cl- + H3O+ loses an
H+ forms gains an
H+ forms
Example 4. In the following reaction, identify the acid and the
base.
H3PO4 loses (donates) = acid
H2O gains (accetps) = acid
H3PO4 + H2O H2PO4- + H3O+
loses an H+
forms gains an H+
forms
Whiteboards Work in pairs
Trade-off marker every question
Partner without the marker should be checking work at each step!
You have 60 seconds to solve the question Show all of your work! Don’t forget units!
Lift board only when prompted
H2O + HF H3O+ + F-
In the above equation, which reactant molecule is the acid?
HI + H2O H3O+ + I-
In the above equation, which reactant molecule is the base?
HSO4- + H2O H2SO4 + OH-
In the above equation, which reactant molecule is the base?
H2PO4- + H2O HPO4
2- + H3O+ In the above equation, which reactant
molecule is the acid?
H2O + NaHCO3- NaCO3
2- + H3O+ In the above equation, which reactant
molecule is the acid?
OH- + HSO4- SO4
2- + H2O In the above equation, which reactant
molecule is the base?
Practice Questions Practice question worksheet
Exit Slip 1. Which of the following are properties of acids?
a. they taste bitter and turn litmus paper blue b. they have a pH of less than 7 and turn litmus paper red
c. they have a pH of greater than 7 and taste sour d. they usually feel slippery like soap
Exit Slip 2. The Bronsted-Lowry definition of a base is
a. a molecule that loses an electron b. a molecule that has a pH of greater than 7
c. a molecule that donates hydrogen ions d. a molecule that accepts hydrogen ions
Exit Slip 3. In the equation, H2O + HI H3O+ + I-, which
reactant molecule acts as the acid? a. H2O b. HI c. H3O+
d. I-
Exit Slip 4. In the equation, H2PO4
- + H2O H3PO4 + OH-, which reactant molecule acts as the base?
a. H3PO4 b. OH- c. H2PO4
-
d. H2O
Exit Slip 5. Why could SO4
2- not act as a Bronsted-Lowry acid? a. because it can donate O2- ions to solution b. because it has no H+ ions to donate to solution
c. because it cannot accept and H+ ions d. pH 2
Homework Finish practice questions