Download acetaminophen c8h9no2

ELEMENTS OF CHEMISTRY I
EXAM II
October 23, 2000
INSTRUCTIONS:
PRINT YOUR NAME ————> NAME
WORK # 1
WORK 5 OF #2 THROUGH #8
SHOW YOUR WORK FOR PARTIAL CREDIT
THE LAST PAGES ARE A PERIODIC TABLE AND A SCRATCH SHEET
R = 0.08206 lit-atm/mol-K
1
R = 8.3145 J/mol
h = 6.626 X 10-34 J-s
c = 2.9979 X 108 m/s
∆Hvaporization for H2O at 100 °C = 40,700 J/mole
2
3
4
5
6
7
8
TOTAL(150)
1. .Define the terms or give a short answer for each of the following
(a) Characterize the following bonds as nonpolar, polar, or ionic. The table at the bottom
of the page might be helpful.
C - F ______________ Mg - O _______________ F- F _______________ S - O ___________
(b) Define electroneganivity :
(c) Circle the more electronegative atom in each pair:
Mg or Ca
B or O
Cs or N
(d) Balance the reaction for the isolation of silicon :
SiCl4 +
Mg ————> MgCl2
If 3 mol of SiCl4 are reacted,
________mol MgCl2
Li or C
+
Si
_________ mol Mg are needed and
and __________ mol Si are produced.
(e) A reaction is ran to produce a drug and 10.89 g of the drug is isolated. Using a
balanced equation, the chemist calculates that if the reaction went perfect, 12.90 g of the
drug would form. Calculate the percent yield for this reaction.
******************************************************************************
Electronegativities of selected elements
H = 2.1
Na = 0.9 Mg = 1.2
C = 2.5
N = 3.0
O = 3.5
F = 4.0
Ti = 1.5
Si = 1.8
P = 2.1
S = 2.5
C l = 3.0
2. Acetaminophen, C8H9NO2, is the active ingredient in Tylenol and is widely used as
an aspirin substitute. An extra strength Tylenol tablet contains of 500 mg of
acetaminophen.
(a) What is the formula weight of acetaminophen.?
(b) How many moles of acetaminophen are in a tablet?
(c) How many individual acetaminophen molecules are in the tablet? (Avogadro’s
number = 6.02 x 1023)
(d) How many moles of carbon atoms are in a tablet?
3. Predict the formula of the ionic compound formed by the following elements or ions.
For the elements, you must determine the charge from the position in the periodic table.
Cation
Anion
Formula
(a) sodium
fluorine
________________
(b) aluminum
hydroxide
________________
(c) magnesium
sulfur
________________
(d) ammonium
sulfate
________________
(e) potassium
hydroxide
________________
(f) lithium
carbonate
________________
4. Disulfur dichloride, S2Cl2, has a revolting smell and it can be used in the vulcanization
of rubber. (Vulcanization is a process that makes rubber stronger.) It can be prepared
by the following reaction :
3SCl2 + 4NaF ————>
SF4 + S2Cl2 + 4NaCl
Determine what mass (g) of sodium fluoride that is required is required to completely
react with 32.7 g of sulfur dichloride, SCl2?
5. Draw a valid Lewis structure for the following molecules of ions.
(a) SO3
(b) NH3
(c) HClO2
(H is bound to O)
(Cl between O's)
(d) SO32-
(e) CH3OH
(has O-H bond)
(f) H2CO
(C is central)
6. Balance the following equations:
(a)
Cr +
(b)
SiO2 +
(c)
NaNO3
+
O2 ————>
C ————>
H2SO4 ————>
(d)
H2 +
(e)
C4H8O +
Cl2 ————>
O2 ————>
Cr2O3
Si +
CO
Na 2SO4 +
HNO3
HCl
CO2 +
H2O
7. Name the following compounds.
(a) Al(OH)3 ______________________
(b) Mg(NO3)2 _____________________
(c) NaF ________________________
(d) Ca3(PO4)2 _______________________
(e) FeSO4 _____________________
use a roman numeral
(g) Na2S_____________________
(f) AlCl3 __________________________
(h) (NH4)2CO3 __________________________
8. In each case, Draw a valid Lewis structure describe the shape of the molecule and indicate
whether the molecule is polar or not. The total number of valence electrons are in parentheses.
Molecule
(a) H2O (8e-)
shape
________________________________
polar or nonpolar
________________________________
(b) O3 (18 e-)
________________________________
________________________________
(c) CF4 (32 e-)
________________________________
________________________________
(d) HCN (10 e-)
________________________________
________________________________