Chem 222 - University of Illinois at...
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Transcript of Chem 222 - University of Illinois at...
Essentials(1) Please register for one lab (out of 5 labs) as well as the
lecture. Unless you register for both of the lab and lecture, no grade will be given to you.
(2) Please properly register for the lab. You can do experiments only in the lab in which you are enrolled.
(3) Please come to the lab you registered for and start your experiments as soon as possible. We have no extra time to make up for labs you missed. If you miss more than two labs, you must drop the course or you will receive a grade E. This will be effective from this Wednesday Jan 12, 2005).
(4) If you miss more than a total of two lectures or labs (total), you will receive a grade E.
(5) Syllabus and other class materials are available at the following Chem 222 website (http://www.chem.uic.edu/chem222/).
(6) Please download Lab Handout (Free) at http://bcs.whfreeman.com/qca/ Click "Experiments" under Student resource. Then, click "Chapters 1-32".
Please come to the lab from today!
• The schedule is very tight• We have only two lab make up
days during the semester You have to finish your lab on time.
• If you don’t show up at the lab, more than twice, you should drop the course.
Web Site Information
• Course Web Sitewww.chem.uic.edu/chem222/
Syllabus, Lab Schedule, Lab Due Date, Report Cover Sheets, KH & DU Lab Handout
• Text Publisher’s Web Sitehttp://bcs.whfreeman.com/qca/Lab Handout (Click Experiments), Sample Chapters 1-5, Spread Sheets etc.
Lab Handout
Information to Survive the Course
Grading Policy. Your final grade in this class is a simple average using the following weights:
50% laboratory All laboratory reports are weighted equally. 50% Quizzes and exams • Several (15-20 min) quizzes will be given
in lecture (10 % of course grade). • Mid-term exam (15 % of course grade) • Final hour exam (25% of course grade). • Questions in the lectures extra points
> 90 →A (~15 %) > 50 →D > 80 →B < 50 →E > 65 →C
A simple linear scaling may be applied if less than 15 % students get A
To Pass the Course• Average of at least 50% on the exams
and quizzes. • You may not miss more than two
labs/classes (total). • In case you have to miss any lab, you
need to inform me and your Lab TA at least one day (24 hours) in advance and obtain permission from me.Otherwise, missed labs will count as zeros.
• In case you have to miss any lecture, you need to inform me at least one day (24 hours) in advance in order to be excused. If not, you lose 5 % of the total grade.
• You must hand in all lab reports for experiments completed, even if you could not analyze your data.
• Missed quizzes, exams, and labs will be given zeros unless I excuse you personally. There are no makeup quizzes or exams.
Not to Lose Your Points
• Please don’t miss any classes or labs. Please do not be late since you will lose some points. (Check the syllabus about the details)
• Academic dishonesty will not be tolerated (Grade E for Overall Grade.)
• If we find that you are disturbing the class (lab or lecture) or performing dangerous practice in lab, your Lab TA or I will request you to leave the class and you will lose your points or may be dismissed.
Some rewards
Class Participation• 2 points for answering
questions in the class
Quizz• 5 Quizzes will be held during
lectures. 20 points each
About the Lab• Read the handout before the class• Prepare your lab notebook before the lab
starts (procedure, calculation; see syllabus about the details) If not, you are not allowed to start
Grading of the Lab• Accurate measurement for unknown
samples• Your lab notebook
(Well organized calculation and graph)• Your lab etiquette will be also graded
(proper use of balance and lab equipment, good lab techniques, and cleaning the lab space.)
Why is Analytical Chemistry Important for You?
• If you plan to be a biologist, a chemist, a environmental scientist, or a medical scientist
→ Analytical chemistry is probably essential.
If you work in a biochemistry lab, you routinely measure
♦ protein concentration♦ pH♦ binding constant♦ complex formationand purify your sample using♦separation by chromatography or
electrophoresis♦detection by UV/visible
spectrometer or fluorescence
Chemical Analysis in Environmental Science
Problems from Ch. 0
1A) What is qualitative analysis?A protocol to identifying [ ] is
present1B ) What is quantitative analysis?
A protocol to identifying [ ] is present
4) What is the purpose of a calibration curve?
5) What is the difference between a homogeneous material and a heterogeneous material?
(hint: composition)
0) What is the meaning of the following terms? (see p9)
Aliquot, Analyte, Aqueous, Masking, Interference,
Abalone seashell
Composite of CaCO3 (99%) and peptides (1%)
1000 Times stronger than a simple mixture of CaCO3 and peptides(actually, stronger than any synthetic materials)
Example of excellent heterogeneous materials
1-1 SI Units(Systeme International d’Unites)
F = ma = [kg] [m/s2] =
This is also called MKS Units(Meter, Kilogram, Second)
Cf. CGS Units(Cm, Gram, Second) If you read papers before 1970, the CGS units are often used.
Using Prefixes as Multipliers (p12)
• Atto-second pulse laser• Pico-mol-scale detection of proteins
by fluorescence spectroscopy• Femto-second terahertz radiation• Nano-science
Usage
Left figure: Electron Micrograph of Peptide nano-tube (id ~ 15 nm)
Memorize prefixes from T(Tera) to a(atto)
Ozone “hole” was formed in Oct of 1993, 1995
17 km =17 × (1 km) = 17 × (103 m) = 1.7× 10 [Q1] m
19 mPa = 19 × (1 mPa) = 19 × (10[Q2] Pa) = 1.9 × 10[Q3] Pa
Unit Conversion (p13)
Q 1-6 How many joures per second and how many calories per hour are produced by a 100-hourse power engine?
E = P*t = (100 horse power) × (1 hour)
= (100 × 745 .7 W) × (60 × 60 s) ~ 268 MJ = 67 Mcal
(1 Big mac is about 600 kcal; note 1 dietary cal = 1 kcal)
Mol, Molarity, Molality ? (p14)
• 1 mol = 6.02× 1023 molecules
ConcentrationMolarity:M = molarity =
Molality:m = molality =
Weight percent =100
solution Lsolute mol
solvent kgsolute mol
solution kgsolute kg
Q1. Tell the definition of solution, solute, and solvent?
Solution: homogenous mixture of substances in a liquid form
Preparing solution (p17)
Molecular weight of NaCl is 58.44 g. How do you prepare the following solution?
1) 0.5 L of 2 M NaCl aqueous solution.
2) 1 m NaCl aqueous solution using the same amount of NaCl as that for (1)
3) 1 wt % of NaCl using the same amount of NaCl as that for (1)
Unit Conversion• Wt % MolarityObtain how much mol of substance
exists in 1L of solutionM =mol/L ↓mol weight=(Wt %/100)×1000d[g/mL]/MW [g/mol]
↑weight of 1L solutiond is the density of the solution• Molality Wt %
Assume in 1L of solution A g of solute and B kgof solvent is included. The molecular mass for the solute is MA.
Molality (m) ≡ (A/MA)/B = A/(MAB)Wt % ≡ 100 A/(1000B + A)
= 100 (A/B)/(1000 + A/B)= 100 mMA/(1000 + mMA)
Diluting solution and unit conversion
Q1) HCl stored in most labs has molarity of 12.1 M. How do you obtain 100 mL of 1 M HCl solution from the solution?
Assume you use y mL of 12.1 M HClsolution
(12.1 M)×(y mL) = (1 M)×(100 mL)
Q2) A typical concentrated NH3 solution contains 28.0 wt % NH3. The density of the solution is 0.899 g/mL. What volume of this reagent should be diluted to 1 L to make 1 M NH3 solution.
NH3 in 1L of solution (g) = 0.899 g/mL × 1000 mL × 0.280 = 251 gObtain the molarity of NH3= 251 (g) /17.03 (g/mol) =14.8 M
Safety
• What do you need to protect your eyes from chemicals?
• Contact lenses are not recommended in the lab. Why?
• You can protect your skin from spills and flames by wearing a flame-resistant lab coat.
• Clean up spills immediately to prevent accidental contact by the next person. How do you clean the spill?
• What do you do if you get spills on your skin.
Treat the spill first by flooding with water. In anticipation of splashes on your body or in your eyes.
Carefully read the section 2-1 of your text.
R1-CO-NH-CHR2 + OH-
R1-COO- + NH2-CHR2
Home work (not graded)
Jan 11 • Ch 0 Ch0: 0-1, 0-4• Ch 1 Ch1: 1-A, 1-B, 1-12, 1-13,
1-14, 1-26, 1-27, 1-28 1-29, 1-31a, 1-33
Read Ch 0-2Particularly, Ch 2Please refresh your memory abouthow to use your tools
