Pavia, Lampman, Kriz, Engelescale Approach to Organric Laboratory Techniques 5/ethis textbook require either of these techniques. If a filtration or decolorizing step isever required, Technique 11 describes these procedures in detail.Pre-Lab Calculations1. Calculate how much 95% ethyl alcohol will be required to dissolve 0.3 g of sulfa-nilamide at 78 C. Use the data for the graph in Technique 11, Figure 11.2 to makethis calculation. The reason for making this calculation is so that you will knowahead of time the approximate amount of hot solvent you will be adding.2. Using the volume of solvent calculated in Step 1, calculate how much sulfanilamidewill remain dissolved in the mother liquor after the mixture is cooled to 0 CTo dissolve the sulfanilamide in the minimum of hot (boiling or almost boiling)solvent, you must keep the mixture at (or near) the boiling point of 95%% ethyl alco-hol during the entire procedure. You wil-likely add more solvent than the amountyou calculated because some solvent win evaporate. Ihe amount of solvent is cal-culated only to indicate the approximate amount of solvent required. You shouldfollow the procedure to determine the correct amount.of solvent needed.CEDUREPreparationsWeigh 0.30 Page 48 1,042 ucrandh this solid to a 10-mL Erlenmeyerlask. Notente cooOneaPurestTarnacrel To a second Erlenmever flask,aEhp144 V697Crystallization: Purification of SolidsTECHNIQUE 11C (Poor solvent)Very soluble atall temperaturesA (Good solvent)Very soluble at elevated temperaturesSparingly soluble at room temperatu reB (Poor solvent)TemperatureFigure 11.1Graph of solubility vs. temperature.at the boiling point of the solvent selected. Theas can be seen250solubility curve should be steep,in line A of Figure 11.1. A curve with a low slopesignificant crystalliza-tion when the temperature of the solution waslowered. A solvent in which the material is verysoluble at all temperatures (line C) also wouldnot be a suitable crystallization solvent. The basicproblem in performing a crystallization is to selecta solvent (or mixed solvent) that provides a steepsolubility-vs.- temperature curve for the materialto be crystallized. A solvent that allows the behav-ior shown in line A is an ideal crystallization sol-vent. It should also be mentioned that solubility200(line B) would not cause1501005060°8040°20°Temperature (C)curves are not always linear,theydepictedin Figure 11.1. This figure represents an idealizedform of solubility behavior. The solubilityfor sulfanilamide in 95% ethyl alcohol, shown inFigure 11.2, is typical of many organic compounds and shows what solubility behav-ior might look like for a real substance. This graph is based on the data in the follow-asareFigure 11.2Solubility of sulfanilamide in 95% ethyl alcohol.curveing table:Solubility (mg/mL)Temperature0°C1420°C2440°C4660°C8880°C210The solubility of organic compounds is a function of the polarities of both thesolvent and the solute (dissolved material). A general rule is "Like dissolves like."If the solute is very polar, a very polar solvent is needed to dissolve it; if the soluteis nonpolar, a nonpolar solvent is needed. Applications of this rule are discussecextensively in Technique 10, Section 10.2, and in Section 11.5.canned, copiedSolubility (mg/mL)Grams soluble-

Question
Asked Oct 8, 2019
37 views

Prelab question

Pavia, Lampman, Kriz, Engel
escale Approach to Organric Laboratory Techniques 5/e
this textbook require either of these techniques. If a filtration or decolorizing step is
ever required, Technique 11 describes these procedures in detail.
Pre-Lab Calculations
1. Calculate how much 95% ethyl alcohol will be required to dissolve 0.3 g of sulfa-
nilamide at 78 C. Use the data for the graph in Technique 11, Figure 11.2 to make
this calculation. The reason for making this calculation is so that you will know
ahead of time the approximate amount of hot solvent you will be adding.
2. Using the volume of solvent calculated in Step 1, calculate how much sulfanilamide
will remain dissolved in the mother liquor after the mixture is cooled to 0 C
To dissolve the sulfanilamide in the minimum of hot (boiling or almost boiling)
solvent, you must keep the mixture at (or near) the boiling point of 95%% ethyl alco-
hol during the entire procedure. You wil-likely add more solvent than the amount
you calculated because some solvent win evaporate. Ihe amount of solvent is cal-
culated only to indicate the approximate amount of solvent required. You should
follow the procedure to determine the correct amount.of solvent needed.
CEDURE
Preparations
Weigh 0.30 Page 48 1,042 uc
randh this solid to a 10-mL Erlenmeyer
lask. Notente cooOneaPurest
Tarnacrel To a second Erlenmever flask,
a
E
hp
144
help_outline

Image Transcriptionclose

Pavia, Lampman, Kriz, Engel escale Approach to Organric Laboratory Techniques 5/e this textbook require either of these techniques. If a filtration or decolorizing step is ever required, Technique 11 describes these procedures in detail. Pre-Lab Calculations 1. Calculate how much 95% ethyl alcohol will be required to dissolve 0.3 g of sulfa- nilamide at 78 C. Use the data for the graph in Technique 11, Figure 11.2 to make this calculation. The reason for making this calculation is so that you will know ahead of time the approximate amount of hot solvent you will be adding. 2. Using the volume of solvent calculated in Step 1, calculate how much sulfanilamide will remain dissolved in the mother liquor after the mixture is cooled to 0 C To dissolve the sulfanilamide in the minimum of hot (boiling or almost boiling) solvent, you must keep the mixture at (or near) the boiling point of 95%% ethyl alco- hol during the entire procedure. You wil-likely add more solvent than the amount you calculated because some solvent win evaporate. Ihe amount of solvent is cal- culated only to indicate the approximate amount of solvent required. You should follow the procedure to determine the correct amount.of solvent needed. CEDURE Preparations Weigh 0.30 Page 48 1,042 uc randh this solid to a 10-mL Erlenmeyer lask. Notente cooOneaPurest Tarnacrel To a second Erlenmever flask, a E hp 144

fullscreen
V
697
Crystallization: Purification of Solids
TECHNIQUE 11
C (Poor solvent)
Very soluble at
all temperatures
A (Good solvent)
Very soluble at elevated temperatures
Sparingly soluble at room temperatu re
B (Poor solvent)
Temperature
Figure 11.1
Graph of solubility vs. temperature.
at the boiling point of the solvent selected. The
as can be seen
250
solubility curve should be steep,
in line A of Figure 11.1. A curve with a low slope
significant crystalliza-
tion when the temperature of the solution was
lowered. A solvent in which the material is very
soluble at all temperatures (line C) also would
not be a suitable crystallization solvent. The basic
problem in performing a crystallization is to select
a solvent (or mixed solvent) that provides a steep
solubility-vs.- temperature curve for the material
to be crystallized. A solvent that allows the behav-
ior shown in line A is an ideal crystallization sol-
vent. It should also be mentioned that solubility
200
(line B) would not cause
150
100
50
60°
80
40°
20°
Temperature (C)
curves are not always linear,
they
depicted
in Figure 11.1. This figure represents an idealized
form of solubility behavior. The solubility
for sulfanilamide in 95% ethyl alcohol, shown in
Figure 11.2, is typical of many organic compounds and shows what solubility behav-
ior might look like for a real substance. This graph is based on the data in the follow-
as
are
Figure 11.2
Solubility of sulfanilamide in 95% ethyl alcohol.
curve
ing table:
Solubility (mg/mL)
Temperature
0°C
14
20°C
24
40°C
46
60°C
88
80°C
210
The solubility of organic compounds is a function of the polarities of both the
solvent and the solute (dissolved material). A general rule is "Like dissolves like."
If the solute is very polar, a very polar solvent is needed to dissolve it; if the solute
is nonpolar, a nonpolar solvent is needed. Applications of this rule are discussec
extensively in Technique 10, Section 10.2, and in Section 11.5.
canned, copied
Solubility (mg/mL)
Grams soluble-
help_outline

Image Transcriptionclose

V 697 Crystallization: Purification of Solids TECHNIQUE 11 C (Poor solvent) Very soluble at all temperatures A (Good solvent) Very soluble at elevated temperatures Sparingly soluble at room temperatu re B (Poor solvent) Temperature Figure 11.1 Graph of solubility vs. temperature. at the boiling point of the solvent selected. The as can be seen 250 solubility curve should be steep, in line A of Figure 11.1. A curve with a low slope significant crystalliza- tion when the temperature of the solution was lowered. A solvent in which the material is very soluble at all temperatures (line C) also would not be a suitable crystallization solvent. The basic problem in performing a crystallization is to select a solvent (or mixed solvent) that provides a steep solubility-vs.- temperature curve for the material to be crystallized. A solvent that allows the behav- ior shown in line A is an ideal crystallization sol- vent. It should also be mentioned that solubility 200 (line B) would not cause 150 100 50 60° 80 40° 20° Temperature (C) curves are not always linear, they depicted in Figure 11.1. This figure represents an idealized form of solubility behavior. The solubility for sulfanilamide in 95% ethyl alcohol, shown in Figure 11.2, is typical of many organic compounds and shows what solubility behav- ior might look like for a real substance. This graph is based on the data in the follow- as are Figure 11.2 Solubility of sulfanilamide in 95% ethyl alcohol. curve ing table: Solubility (mg/mL) Temperature 0°C 14 20°C 24 40°C 46 60°C 88 80°C 210 The solubility of organic compounds is a function of the polarities of both the solvent and the solute (dissolved material). A general rule is "Like dissolves like." If the solute is very polar, a very polar solvent is needed to dissolve it; if the solute is nonpolar, a nonpolar solvent is needed. Applications of this rule are discussec extensively in Technique 10, Section 10.2, and in Section 11.5. canned, copied Solubility (mg/mL) Grams soluble-

fullscreen
check_circle

Expert Answer

Step 1
  1. The solubility of sulfanilamide in 95% ethyl alcohol at 780C can be known from the figure 11.2 as given below.
help_outline

Image Transcriptionclose

250 200 150 100 50 20° 80 40° 60° Temperature (°C) Solubility (mg/mL)

fullscreen
Step 2

Therefore, the solubility of sulfanilamide in 95% ethyl alcohol at 780C is found out from the above figure to be 180 mg/mL. This implies that in 1 mL of 95% ethyl alcohol 180 mg of sul...

help_outline

Image Transcriptionclose

1mL -x3 00 mg 1.67 mL 180mg Therefore, the amount of 95% ethyl alcohol will be required to dissolve 0.3 g of sulfanilamide at 78°C is 1.67 mL

fullscreen

Want to see the full answer?

See Solution

Check out a sample Q&A here.

Want to see this answer and more?

Solutions are written by subject experts who are available 24/7. Questions are typically answered within 1 hour.*

See Solution
*Response times may vary by subject and question.
Tagged in

Science

Chemistry

Other

Related Chemistry Q&A

Find answers to questions asked by student like you
Show more Q&A
add
question_answer

Q: Propose you are given a mixture of naphthalene, propanoic acid, and diethyl amine. Explain, using a ...

A: The chemical compounds Napthalene, propanoic acid and diethyl amine present in given mixuture is sep...

question_answer

Q: Determine the mass of oxygen in a 7.4-g sample of Al(NO3)3 Express your answer to two significant fi...

A: The mass of O present in 7.4 g of given Al(NO3)3 sample is determined by considering the given sampl...

question_answer

Q: For the zeroth-order reaction: C → products, -Δ[C]/Δt = k, which of the following graphs would be ex...

A: Rate of reaction represents the change of concentration of a reactant or a product with respect to t...

question_answer

Q: An 8.65-g sample of an unknown group 2A metal hydroxide is dissolved in 85.0 mL of water. An acid-ba...

A: The values are given as follows:

question_answer

Q: How do you know what (chemicals, molecules, substances) to place over the arrow?

A: The reaction is:

question_answer

Q: I need help on Question 1.

A: Click to see the answer

question_answer

Q: The endothermic decomposition of magnesium oxide is described in the chemical equation below.   2MgO...

A: Reaction for which the enthalpy change has to be determined is the reverse of the given reaction wit...

question_answer

Q: What NaCl concentration results when 304 mL of a 0.770 M NaCl solution is mixed with 447 mL of a 0.2...

A: Given information:V1 = 304 mLV2 = 447 mLM1 = 0.770 MM2 = 0.240 M

question_answer

Q: In the reaction: P4 + 6Cl2 = 4PCl3, if the actual amount of PCl3 recovered is 16.25 g, what is the p...

A: According to the given reaction 4 mol of PCl3 is formed.The mass of PCl3 corresponds to 4 mol PCl3 =...