Practice In-class Test 2 for CHM151: Instructor, Ken Costello Equation Balancing, Classification, Prediction of Products,

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Practice In-class Test 2 for CHM151 Instructor,
Ken CostelloEquation Balancing, Classification,
Prediction of Products, Stoichiometry
10 mg 1 mol deci 2.49 mmol
dL 40.1 g 0.1 L
Change the blood test reading for calcium from
conventional to world standard of mmol/L.
80 mg 1 mol 0.001 .0143 mol
dL 55.8 g milli L
Change the blood test reading for iron from
conventional to molarity (M is mol/L).
80 mg 1 dL 0.001 0.08 wt/vol
dL 100 mL milli
Change this blood test reading for cholesterol
from conventional to wt/vol
40 ng 10-9 µ milli 40 ppb
mL nano 10-6 0.001
Change this blood test reading for Vitamin D from
conventional to ppb (µg/L)
Sodium hydroxide (lye) can be used in closed
environments to remove excess CO2 gas. The
balanced chemical equation is
2NaOH(s)  CO2(g) --gt  Na2CO3(s)
 H2O(g) Ace Hardware has these in one pound
bottles. What mass of CO2(g) will the bottle be
able to absorb?
Potassium nitrate decomposes on heating,
producing potassium oxide and gaseous nitrogen
and oxygen.                                  4KNO3
(s) --gt 2K2O(s) 2N2(g) 5O2(g) We need to
breath about 1 gram of oxygen (O2) per minute. A
pound of KNO3 would provide how many minutes of
oxygen?
2
Write what type of reaction it is and balance the
following chemical equations.
2AlCl3 3Ca ? 3CaCl2 2Al
Single replacement Decomposition Double
replacement Combustion Synthesis (combination)
2KClO3 ? 2KCl 3O2
2NaCl MgSO4 ? Na2SO4 MgCl2
CH3CH2OH 3O2 ? 2CO2 3H2O
CaO H2O ? Ca(OH)2
Synthesis (Combination) Reactions SYNTHESIS OF
FLAVORINGS
Ester
Write the synthesized esters in shorthand formulas
Acetic acid (vinegar)
Propanol (propyl alcohol)
Propyl acetate gt pear flavor
O
H
H
H
H
C
C
C
O
C
H
C
H
H
H
H
H
Water is released
O
O
CH3-CH2-CH2-OH CH3C-OH ? H2O
CH3CH2CH2-O-CCH3
O
Example
H2O
OH

O
H2O

OH
Benzyl alcohol (globs in lava lamps)
acetic acid ? water Benzyl acetate (peaches,
strawberries)
H2O

OH
Isopentenyl alcohol acetic acid ? water
Isopentenyl acetate (Juicy-Fruit)
O
HO
OH
H2O

HO
Amyl alcohol (oil of potato spirit)
salicylic acid (wart remover)
? water Amyl salicylate (Pineapple flavor)
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Practice Test 2 for CHM130LL Instructor, Ken
CostelloEquation Balancing, Classification, and
Prediction of Products
O
O
H
K
H
C
C
Cl
Cl
O
O
C
O
K
H
O
O
O
H
O
With heat, potassium perchlorate will release
oxygen atoms that will attack the acetic acid and
turn it into carbon dioxide and water vapor.
Potassium chloride will be a salt residue. The
atoms on the right dont match the number we
started with. What two other molecules should be
shown?
H
O
O
C
O
H
O
C
O
O
H
C
H
H
H
Ethanol will burn in oxygen forming carbon
dioxide and water. How many carbon dioxide
molecules will form? ____ How many waters will
form? ____ How many pairs of oxygen are
needed? _____
O
Ba
O
O
Ca
S
O
O
H
H
O
Ba(OH)2(aq) CaSO4(aq) ? BaSO4(s)
Ca(OH)2(aq)Draw the products of this double
replacement reaction.
(NH4)2Cr2O7 ? N2 4H2O Cr2O3 Draw the products
of this decomposition reaction.
O
O
N
N
Cr
Cr
O
O
O
O
O
Mg(s) 2Ag(aq) 2NO3-(aq) ? 2Ag(s) Mg2(aq)
2NO3-(aq) Draw the products of this single
replacement reaction.
Ag
Mg
Ag
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ACTIVITY SERIES
Stable
Li
K
Ca2
Na
Mg2
Al3
Zn2
Cr3
Fe3
2H
Cu2
Ag
Hg2
Cr2O72-14H
Cl2
MnO4-8H
Au3
O2
F2
Oxidizers
Reducers
Lithium
Potassium
Calcium
Sodium
Magnesium
Aluminum
Zinc
Chromium
Iron (Fe)
H2
Copper
Silver (Ag)
Mercury
2Cr3 7H2O
2Cl-
Mn2 4H2O
Gold
2O2-
2F-
Stable
Single replacement reactions are based on
elements either giving up electrons or taking
electrons. Complete and balance the below
reactions.
Zn 2H(aq) ? Zn2(aq) H2(g) 2Al 6H(aq) ?
2Al3(aq) 3H2(g) 2Fe 6H(aq) ? 2Fe3(aq)
3H2(g) 2Hg(s) O2(gas) ? 2HgO(s) 3Ca(s)
2Al3(aq) ? 3Ca2(aq) 2Al(s) Ag(s)
Cl2(g) ? 2AgCl(s) Au(s) Cl2(g) ?
NR Ca2(aq) Ag(aq) ? NR Fe Ag ? NR
Mg(s) 2AgNO3(aq) ? 2Ag(s) Mg(NO3)2(aq)
Single replacement only occurs if the element on
the right is below the element on the left.
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• Ingredients to make an emergency low power
  battery.
• A metal that sits above H on the activity scale
  (it will be dissolved by H).
• A metal that sits below the H on the activity
  scale or carbon (such as the graphite in a
  pencil). It wont be affected by the H.
• An acid.
• List 4 metals that you are likely to find that
  sit above H on the activity scale and say what
  object that may be made from that metal
• Zinc (galvanized nail, galvanized sheet metal)
• Chromium (any chrome plated object)
• Aluminum (soda can, aluminum foil, any object
  made of aluminum)
• Iron (nail or any rusty object)
• List 3 metals that you are likely to find that
  sit below H on the activity scale and say what
  object that may be made from that metal
• Copper (penny or copper wire)
• Silver (any silver jewelry)
• Gold (any gold or gold plated jewelry or object)
• List 5 acids that you are likely to find and what
  item may contain that acid.
• Phosphoric acid (potato, Coca-cola and other
  sodas).
• Citric acid (any citrus such as lemons, oranges,
  grapefruit)
• Acetic acid (vinegar)
• Sulfuric acid (dead car battery)
• Hydrochloric acid (stomach acid)

Electronic device
e-
e-
e-
Metal that doesnt react with H
H2(g)
Metal that gives electrons to H
Fruit, vegetable, or solution that contains the
H acid
e-
M
M
H
e-
M
As metal dissolves, it gives up electrons that
travel through device to the other side.
e-
H
H
The acid (H) picks up electrons and becomes
hydrogen gas