South Pasadena • Chemistry
Name
Period
Date
Semester 1 Review
UNIT
1
•
MEASUREMENTS
AND
DENSITY
The following measurements were taken of a rectangular Calculate the density of the block in g/cm3, recording
block of an unknown metal.
your answer with the correct significant figures.
V = ℓ × w × h = (5.45 cm)(4.32 cm)(1.00 cm)
= 23.5 cm3
• Electronic balance reading (in g):
m = 204.8 g
m
204.8 g
D=
=
= 8.71 g/cm3
V 23.5 cm3
Write this measurement in scientific notation:
2.048 × 102 g
Which of the following could be the unknown metal?
• Aluminum d = 2.70 g/cm3
• Length, width, and height of the block. Write your
• Copper
d = 8.94 g/cm3
measurements.
• Gold
d = 19.32 g/cm3
• Silver
d = 10.49 g/cm3
1
2
3
4
5
cm
5.45
cm
Calculate the Percent Error of your calculated density.
| calculated − accepted |
1
2
3
4
5
cm
% error =
× 100%
4.32
cm
accepted
|8.71 g/cm3 − 8.94 g/cm3|
1
2
3
4
5
cm
=
× 100% = 2.6%
1.00
cm
8.94 g/cm3
204.8
Does the percent error describe the accuracy or
precision of your calculated value? Explain briefly.
% error describes accuracy because it tells you how
far your value is to the actual/accepted value.
Semester 1 Review
UNIT
1
•
DIMENSIONAL
ANALYSIS
Perform the following conversions. Show all your work.
3.1 wks = ? min
0.350 dL = ? L
7
days
24
hours
60
min
⎞⎟ ⎛⎜
⎞⎟ ⎛⎜
⎞⎟ = 31,248 min 0.350 dL⎛⎜ 1 L ⎞⎟ = 0.0350 L
3.1 weeks ⎛⎜
⎝1 week⎠ ⎝ 1 day ⎠ ⎝ 1 hour ⎠
⎝10 dL⎠
208 cm3 = ? in3
(1 inch = 2.54 cm)
1
in
⎞⎟ ⎛⎜ 1 in ⎞⎟ ⎛⎜ 1 in ⎞⎟ = 12.7 in3
208 cm3 ⎛⎜
⎝2.54 cm⎠ ⎝2.54 cm⎠ ⎝2.54 cm⎠
12.6 m = ? km
1 km ⎞
12.6 m ⎛⎜
= 0.0126 km
⎝1000 m⎟⎠
1.4 m/s = ? km/h
1.4 m ⎛ 1 km ⎞ ⎛ 60 s ⎞ ⎛60 min⎞
= 5.04 km/h
s ⎜⎝1000 m⎟⎠ ⎜⎝1 min⎟⎠ ⎜⎝ 1 hr ⎟⎠
–20°C = ? K
K = °C + 273 = (−20°C) + 273 = 253 K
Semester 1 Review
UNIT
Complete the following table:
Atomic
Isotope
Number
•
ELEMENTS
Mass
Number
Number of
protons
Number of
neutrons
Number of
electrons
Net Charge
17
37
17
20
18
−1
Ca
20
44
20
24
20
0
Fe2+
26
57
26
31
24
+2
37
Cl–
44
57
2
Classify each element above as:
hydrogen, alkali metal, alkaline earth metal, transition metal,
inner-transition metal, other metal, non-metal, halogen, noble gas
Cl is halogen, Ca is alkaline earth metal, Fe is transition metal
List the seven diatomic elements:
H2, N2, O2, F2, Cl2, Br2, I2
Semester 1 Review
UNIT
Consider the compound Ba(NO3)2.
•
Classify:
•
•
[ Ionic | Covalent | Acid | Organic ]
2
•
COMPOUNDS
Consider the compound N2O5.
•
Classify:
Name the compound: barium nitrate
•
Name the compound: dinitrogen pentoxide
Calculate the Molar Mass.
Ba: 1 × 137.33 = 137.33
N: 2 × 14.01 = 28.02
O: 6 × 16.00 = 96.00
Molar Mass: = 261.35 g/mol
•
Calculate the Molar Mass.
N: 2 × 14.01 = 28.02
O: 5 × 16.00 = 80.00
Molar Mass: = 108.02 g/mol
•
Calculate the percent O in N2O5.
80.00 g
%O =
× 100% = 74.06%
108.02 g
•
How many molecules of N2O5 are in a 19.5 L
sample at STP?
1 mol ⎞ ⎛6.022 × 1023 molecules⎞
19.5 L ⎛⎜
⎟⎠
1 mol
⎝22.4 L⎟⎠ ⎜⎝
23
= 5.24 × 10 molecules
•
Calculate the percent O in Ba(NO3)2.
96.00 g
%O =
× 100%= 36.73% O
261.35 g
•
What is the mass of 0.46 mol Ba(NO3)2
261.35 g⎞
0.46 mol ⎛⎜
= 120 g
⎝ 1 mol ⎟⎠
[ Ionic | Covalent | Acid | Organic ]
Semester 1 Review
UNIT
3
•
NAMING
ORGANIC
COMPOUNDS
Fill in this chart of formulas and names of hydrocarbons:
C3H 8
Propane
C9H18
nonene
C5H10
Pentene
Draw the molecule for 2,3,3-trimethyloctane.
H
H
CH3 CH3 H
H
H
H
H
C
C
C
C
C
C
C
C
H
H
CH3 H
H
H
H
H
H
H
Br
C
C
C
C4H 6
butyne
What is the name of this hydrocarbon?
H
3-methylhexane
Name the following compound:
H
C6H14
hexane
Draw all the isomers for the compound on the left.
(There are three.)
H
H
H H Br
1,1-dibromopropane
Br
Br
H
C
C
C
H
H
H
H
H
H
Br
H
Br
C
C
C
H
H
H
H
Br
H
C
C
C
H
Br
H
H
H
Semester 1 Review
UNIT
3
•
FUNCTIONAL
GROUPS
Label these pictures with the type of functional group:
Aldehyde
Ether
Ester
Alcohol
Carboxylic acid
Ketone
Look at the carboxylic acid and the alcohol molecules. (1) Label these two molecules as “alcohol” and
“carboxylic acid”. (2) Draw a BOX around the atoms that will form H2O. (3) Draw the products that form.
(4) When they react, they form an ______________ .
" H
carboxylic acid
alcohol
H
O
C
C
O
H
ester
H
H
C
C
H
H
O
H +
H
H
Semester 1 Review
UNIT
4
•
NAMING
COMPOUNDS
Classify each compound as Ionic (I), Covalent (C), or Acid (A). Write the names or formulas for each compound.
Name
Type
Formula
Name
Type
Formula
Ca2+ ClO3−
Calcium chlorate
I
Phosphorus
pentachloride
C
PCl5
Ammonium sulfide
I
(NH4)2S
Sn(Cr2O7)2
Ferrous phosphate
iron(II) phosphate
I
Fe3(PO4)2
N 2O
Carbonic acid
A
H2CO3
Sodium sulfate
I
Na2SO4
Ca(ClO3)2
H+
Hydrochloric acid
A
Cl−
HCl
Sn4+ Cr2O72−
Stannic dichromate
I
Dinitrogen monoxide
C
Pb2+ C2H3O2−
Lead acetate
I
Pb(C2H3O2)2
Semester 1 Review
UNIT
4
•
CONCENTRATIONS
Consider a solution of Ba(OH)2. Show your work for each of the following.
• Calculate the concentration when 0.25 mol Ba(OH)2 is used to prepare a 120 mL solution.
n = 0.25 mol
V = 0.120 L
M=?
n 0.25 mol
M= =
= 2.1 M
V 0.120 L
•
•
•
Calculate the volume of a 1.20 M solution if 151.0 g Ba(OH)2 is dissolved.
MM = 1(137.33) + 2(16.00) + 2(1.008) = 171.49 g/mol
1 mol ⎞
n = 151.0 g ⎛⎜
= 0.8805 mol
V=?
M = 1.20 M
171.49
g⎟⎠
⎝
n
0.8805 mol
V= =
= 0.734 L
M
1.20 M
How many mL of a 3.0 M Ba(OH)2 solution is required to prepare a 40.0 mL sample of 0.20 M solution?
Mconc = 3.0 M
Vconc = ? mL
Mdil = 0.20 M
Vdil = 40.0 mL = 0.0400 L
Mconc × Vconc = Mdil × Vdil
à
(3.0 M)(Vconc) = (0.20 M)(0.0400 L)
Vconc = 0.00267 L = 2.67 mL
Write the equation for how Ba(OH)2 dissolves in water.
Ba(OH)2 " Ba2+ + 2 OH− (Strong base)
Semester 1 Review
UNIT
4
•
ACIDS/BASES
Match the terms with the following statements. Each term may be used once, more than once, or not at all.
a) acid
b) base
c) both acid and base
d) neither acid nor base
A
1.
pH = 5
B
9.
B
2.
tastes bitter
B
10. alkaline
C
3.
electrolyte
A
11. tastes sour
A
4.
vinegar, HC2H3O2
B
12. turns cabbage juice blue, green, or yellow
B
5.
increases [OH ]
B
13. household ammonia
A
6.
neutralizes NaOH
D
14. pH = 7
B
7.
feel slippery
C
15. can burn your skin
D
8.
Na2SO4
B 16.
−
milk of magnesia, Mg(OH)2
high pH
A 1.0 x 10-4 M solution of HCl has a pH of 4.00 and a pOH of 10.00.