Lab final now son! Flashcards
(182 cards)
1
Q
A
methyl alcohol
2
Q
What should you do if something gets in your eye?
A
Remember that the first aid you give yourself is critical. Every second counts dont forget to help your neighbor- your neighbor cant see! Hold the eyelid open while flushing the eye with water from the eyewash for about 15 minutes and then see a doctor immediately.
3
Q
draw structure
Biphenyl
neutral
A
4
Q
What are the inorganic compounds used in the solubility experiment?
A
Water - H2O
5
Q
what is the formula to calculate molality?
A
m=moles of solute/kg of solvent
6
Q
A
trans-cinnamic acid
weak acid
7
Q
Who should be called immediately for assistance in case of an accident or injury in the laboratory?
A
The lab instructor. If for some reason the laboratory instructor is away then the laboratory assistant or a staff member.
8
Q
A
9
Q
A
salicylic acid
10
Q
draw structure
Hexane
base
A
11
Q
A
succinic acid
12
Q
How can you eliminate the possibility of your Bunsen burner becoming a fire hazard?
A
It should be burning only when it is being used. It should be carefully positioned so that the flame will not burn overhanging shelves, books, paper, or its own tubing. No flammable chemicals should be in the vicinity
13
Q
A
cyclohexene
14
Q
A
acetanilide
15
Q
draw structure
3-nitrophthalic acid
weak acid
A
16
Q
what ORGANIC material was used in the Distillation Lab?
A
Isopropyl Alcohol
n-Butyl Alcohol
Methyl Alcohol
Sec-Butyl Alcohol
n-Amyl Alcohol
n-Hexyl Alcohol
17
Q
What is the melting point range of a pure sample?
A
a pure sample exhibits a melting point range of a one to three degree difference between the point at which the first crystal begins to melt, and the temperature at which the last crystal is completely melted.
18
Q
draw structure
o-xylene
A
19
Q
Describe how to distinguish an open fire in the laboratory.
A
Discharge small fire extinguisher at base of flames slowly and systematically moving from one side to the other to avoid flashback while calling for assistance. If not immediately brought under control have fire department called while using larger back-up extinguishers and evacuating nonparticipants. Do not stay in the laboratory if fire continues to spread.
20
Q
A
carbon disulfide
21
Q
When does boiling occur?
A
when vapor pressure and atmospheric pressure are equal
22
Q
Define Azeotrope.
A
a constant boiling mixture of two or more components with a definite composion usually boiling below the lowest boiling point or sometimes above the highest boilng point but never inbetween
23
Q
draw structure
ethyl acetate
A
24
Q
A
25
# draw structure
azobenzene
26
# draw structure
_t_-amyl alcohol
27
# draw structure
phenol
weak acid
28
# draw structure
sulfuric acid
strong acid
29
4-chlorocyclohexene
30
# draw structure
4-chlorocyclohexene
31
indicate whether the following pairs of compounds will be miscible or immiscible in one another.
zinc chloride and water
CH3COOH and water
Urea and diethyl ether
miscible
miscible
immiscible
32
# draw structure
aminohydroxyethane
33
describe step by step how one prepares a sample for a melting point.
1. clamp thiele tube to a ring stand
2. fill thiele tube with mineral oil 1/2 inch above side arm
3. fit thermometer through thermometer adapter
4. make rubberband by cutting a slice of rubber tubing
5. clamp the thermometer adapter above thiele tube
6. obtain 2mm sample in capillary tube
7. attach capillary tube adjacent to the bottom of the thermometer
8. position thermometer bulb and sample so that they are centered in the thiele tube
34
35
why was phosphiric acid used in the dehydration lab instead of sulfuric acid?
since the latter will cause charring and give off noxious fumes
36
_n_-hexyl alcohol
37
what is the difference between simple distillation and fractional distillation? give a scenario for which each technique is appropriate.
- simple distilation may be used if two compounds differ greatly in boiling point and thus in vapor pressure, the mixture may then be seperated into two components fairly well
- fractional distillation is used to seperate liquids when more effeciancy is need then may be obtained by simple distillation
- fractional distillation a series of simple distillations carried out at one time using a fractional column
38
_m_-nitroaniline
39
Why are unauthorized experiments not permissible?
No student knows for certain that an unauthorized experiment is safe. Discovered infractions will result in suspension from the lab
40
# draw structure
_sec_-butyl alcohol
41
azobenzene
42
camphor
43
# draw structure
_n_-amyl alcohol
44
what are the characteristics of a good chaser solvent?
- boiling point approximately 50º higher than the product
- must not react with reactants or products
- must be easily detected
45
# draw structure
_endo_-norbornene-_cis_-5,6-dicarboxylic acid
strong acid
46
carbon disulfide
47
Uera
Base
48
ethylene glycol
49
# draw structure
phosphoric acid
strong acid
H3PO4
50
# draw structure
isopropyl alcohol
51
# draw structure
salicylic acid
52
Give names of 6 common extremely flammable solvents and precautions in their use.
Diethyl ether, petroleum ether, ligroin, acetone, benzene, and ethyl acetate are six common extremely flammable solvents. Always pour these chemicals with care. When using them at your desk, be sure that all flames and spark sources in the area are turned off.
53
54
ethyl acetate
55
Biphenyl
neutral
56
_t_-amyl alcohol
57
What is the liklihood of an impure sample being a eutectic mixture?
one in a hundred
58
How do you calculate % recovery?
%recovery= (weight of solid/ 1 gram) X 100%
59
What type of clothing is safest in the laboratory
No synthetics which are not frilly or flared and do not have lose, flowing sleeves or scarves are the safest. Synthetics, in general, burn readily and stick to you on melting, causing much worse burns. Shorts and tank tops are not allowed because they do not offer much protection. Lab coasts or aprons are strongly recommend
60
isopropyl alcohol
61
What footwear is needed in the laboratory?
Low heeled, leather or equivalent, shoes with no open spaces. Open shoes permit spills to get in the feet and will not be allowed in the lab
62
H3PO4
phosphoric acid
strong acid
63
Describe the proper way to heat a test tube and its contents
Point the test tube away from yourself and others. Oscillate the tube while gently heating to prevent "bumping"
64
phenol
weak acid
65
acetic acid
66
diphenyl phthalate
67
benzoic acid
68
_n_-butyl alcohol
69
What should be worn in a laboratory at all times to decrease the likelihood of eye injury?
Approved glasses or goggles.
70
what information about a compound can one obtain from melting point data?
purity
identity of a compound
molecular weight
71
# draw structure
Uera
Base
72
If a mixture of two compunds is heated, the vapor pressure of both compounds in the vapor equal to?
the ratio of the vapor pressure in the compounds
73
What is the procedure to perform a solubility lab?
1. Add 1 mL of purified H2O at room temperature to test tube containing 50 mg of biphenyl.
2. Add 1 mL of ethyl alcohol at room temperature to test tube containing 50 mg of biphenyl.
3. Add 1 mL of hexane at room temperature to test tube containing 50mg biphenyl.
4. Mix well
5. Record solubility ( soluble, partially soluble, or insoluble).
6. Heat each mixture to boiling point using steam cone.
7. Record results.
8. From results determine the polarity of the solvent being used. ( Polar, moderately polar, or nonpolar)
9. Repeat procedure using sodium acetate and 3-nitrophthalic acid.
74
_n_-butyl alcohol
75
# draw structure
cyclohexonal
76
Why is smoking, chewing, eating, or drinking not permissible for individuals performing an experiment in the laboratory?
Smoking is not permitted because of the fire hazard. None of the above are allowed because of the possibility of getting chemicals in the mouth
77
carbon tetrachloride
78
Hexane
base
79
what is used to dry distillation apparatus before each distillation?
acetone
80
81
# draw structure
Benzenesulfoic acid
weak acid
82
What are the organic compounds used in the melting point lab?
urea
_trans_- cinnamic acid
83
# draw structure
acetanilide
84
Under what conditions are contact lenses permissible in the laboratory?
They are permissible only if one wears approved goggles. Glasses give good protection from splashes only from the front. Anything getting under contact lens will not wash out until the lense is removed. By then the eye could be damaged.
85
# draw structure
4-bromoacetanilide
86
What are the organic compounds used in the crystalization lab?
endo-norbornene-cis-5, 6-dicarboxylic acid
87
_o_-xylene
88
Solvents for crystalization should have what four characteristics?
1. the compound being purified must be soluble in hot solvent and much less soluble in cold solvent.
2. the impurities must be soluble in cold solvent or insoluble in hot solvent
3. the solvent should be easily removed from the compound (low boiling)
4. The solvent must not react with the compound being purified
89
How can a small contained fire be put out simply?
Smother the fire with an inverted beaker. In case of a multineck flask, loosely insert rubber stoppers or corks.
90
What are the organic compounds used in the extraction lab?
fluorenone
benzenesulfonic acid
phthalic acid
phenol
aniline
diethyl ether
91
# draw structure
methyl alcohol
92
# draw structure
acetone
93
Distillation is a technique based on the ______ of the components by \_\_\_\_\_\_\_\_\_
separation, boiling
94
95
# draw structure
sucrose
96
# draw structure
succinic acid
97
# draw structure
Aniline
weak base
98
99
how do you separate compounds in the extraction lab?
1. this is accomplished by dissolving a mixture of organic compounds in a solvent which is immiscible with water
2. then a quantity of aqueous weak base is mixed with the solution
3. the weak base will react with all the stronger organic acids
4. the aqueous layer is separated from the solvent layer and acidified and it precipitates
5. the solid is filtered and dried
6. Weaker organic acids may be removed by using a strong base followed by acidification of the aqueous layer
7. organic bases may be removed from the solution using an acid followed by the addition of a base to aqueous layer
8. All neutral organic compounds remain in the solvent layer
100
# draw structure
1-octacosanol
101
What is the narrow melting point range of a pure sample referred to as?
Sharp melting point
102
what compound was used to remove the last traces of water in the dehydration lab?
anhydrous sodium sulfate
103
# draw structure
Fluorenone
neutral
104
# draw structure
_n_-hexyl alcohol
105
What is the accuracy of the Rast method of determining molecular weights?
+/- 10% actual molecular weight
106
What are some different techniques used to aid in crystallization?
1. Scratching the interior surface of the flask with a stirring rod
2. putting a stirring rod into the solution and letting the solvent evaporate and then reintroducing the stirring rod
3. adding a boiling stone to the solution
107
1-octacosanol
108
A rast molecular weight determination of an unknown organic compoind involved 50.1 mg of solute and 0.7428g of solvent. This mixture of solute-solvent produced a melting point range of 157-164º. Pure camphor, the solvent, melts at 171.5-173º and has a cryoscopic constant of 39.7ºC kg/mol.
MW=_1000kg X 0.05010g X 39.7kg/mo_l
(173-164) X 0.74280g
MW= 297.52g/mol
\* don't forget to check that your rast mw is within the 10% range on the test\*
109
sucrose
110
cyclohexonal
111
What are the inorganic structures used in the extraction lab?
sodium hydroxide- NaOH
Sodium Chloride - NaCl
Hydrochloric Acid- HCl
Sodium Sulfate- Na2SO4
Water- H2O
112
# draw structure
_n_-butyl alcohol
113
sodium acetate
114
Why should we never pipet chemicals with our mouth?
Because you can easily suck the chemicals into your mouth. A pipetting bulb should always be used.
115
_endo_-norbornene-_cis_-5,6-dicarboxylic acid
strong acid
116
# draw structure
cyclohexene
117
acetone
118
sulfuric acid
strong acid
119
Why should the labels on the reagent bottles be read carefully before using?
Adding the wrong reagent could be dangerous. The wrong regent will not give proper results
120
m-nitroaniline
121
sodium bicarbonate
weak base
122
# draw structure
diphenyl phthalate
123
# draw structure
_trans_-cinnamic acid
weak acid
124
# draw structure
common: methyl alcohol
IUPAC: methanol
125
What factors affect the solubility of one compound in another?
polarity
temperature
surface area
126
# draw structure
camphor
127
Why must reagents be added slowly and with caution?
In order to keep a reaction under control. A large amount of a chemical being added all at once might result in a violent reaction(explosion)
128
What is a eutectic mixture?
a specific ratio for two or more compounds which furnish a sharp melting point
129
What are the organic compounds used in in the solubility experiment?
Biphenyl
ethyl alcohol
hexane
sodium acetate
3-nitrophthalic acid
130
# draw structure
ethylene glycol
131
# draw structure
ethyl alcohol
strong acid
132
# draw structure
acetic acid
133
Aniline
weak base
134
# draw structure
Phthalic acid
135
# draw structure
m-nitroaniline
136
What is indicative of an impure sample in the melting point lab?
a wide melting point range that occurs over 4-10° or more
137
# draw structure
carbon tetrachloride
138
# draw structure
_n_-butyl alcohol
139
Benzenesulfoic acid
weak acid
140
What is distillation?
one of the most widely used pruification technique in organic chemistry
This technique is based on the separation of the components by boiling point.
141
Phthalic acid
142
# draw structure
_m_-nitroaniline
143
extraction is an effective method for selectively separating the following types of organic compounds in a mixture:
1. all stronger organic acids
2. all weaker organic acids
3. all organic bases
4. all organic neutral compounds
144
4-bromoacetanilide
145
# draw structure
benzoic acid
146
_n_-amyl alcohol
147
What precautions are needed with long hair, beards, and neckties in the laboratory?
These may easily catch fire, get into chemicals, or get caught in the apparatus. Secure long hair. Do not wear ties
148
149
aminohydroxyethane
150
what INORGANIC were used in the dehydration of alcohol lab?
Sulfuric Acid- H2SO4
Water-H2O
Sodium Sulfate-Na2SO4
Phosphoric Acid-H3PO4
Sodium Chloride-NaCl
151
What are colligative properties?
What are four examples of colligative properities?
colligative properties are properties that depend only upon the number of solute particles in a solution and not on the identity of those particles.
1. freezing point depression
2. boiling point elevation
3. vapor pressure
4. osmotic pressure
152
what ORGANIC compounds were used in the dehydration of alcohols lab?
Cyclohexene
Acetone
Cyclohexanol
O-xylene
153
# draw structure
carbon disulfide
154
ethyl alcohol
strong acid
155
Fluorenone
neutral
156
What is one industrial method of preparing olefins?
What does this method involve?
acheived by the dehydration of alcohols
this method involves heating the alcohol with an acid catalyst and distilling the product
157
Why is it important to read and study each experiment before performing it?
This enables you to know what hazards are involved, proper precautions to observe, and how to handle and dispose of flammable or otherwise hazardous materials
158
What is the diacid used in the crystalization experiment?
_endo_-norbornene-_cis_-5,6-dicarboxylic acid
159
common: methyl alcohol
IUPAC: methanol
160
3-nitrophthalic acid
weak acid
161
# draw structure
sodium bicarbonate
weak base
162
# draw structure
carbon disulfide
163
# draw structure
sodium acetate
164
What should be used immediately if clothing catches fire or if a chemical is spilled on the clothing.
You should immediately douse yourself with-water at the safety shower. Dont forget to help your neighbor- your neighbor is in real trouble. Clothing should be removed in case of a large chemical spill.
165
_sec_-butyl alcohol
166
diethyl ether
167
ligroin
168
# Draw structure
ligroin
169
petroleum ether
170
# Draw structure
petroleum ether
171
Strong Acids
* HCl
* HBr
* HI
* H2SO4
* HNO3
172
Weak Acids
* HF
* HNO2
173
Strong Base
* NaOH
* KOH
* Ba(OH)2
* Na2SO4
174
Weak Base
* NaHCO3
* KHCO3
175
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177
178
179
180
181
182
