153. (Nuclear chemistry) To
balance the equation 230Th --> 4He + 226
the other element produced is
Ra, Rn, Po
154. (Logarithms, nuclear
chemistry, half-lives) Demonstration: Pass out semilog paper and have students
plot the following data for decay of a Tc isotope. What is the approximate
half life in hours?
4, 6, 8
Demonstration: Draw or obtain a rectangle. Measure one side of the rectangle
carefully to 3 significant figures, and measure the other side of the rectangle
to only 1 significant figure. Ask the class what the area of the rectangle
is based on your measurements.
What is the area of a rectangle that is 3 m by 1.11 m?
3.33 m2, 3 m2
The following columns of substances are listed as a combination of pure
substances and mixtures. Which column represents mostly pure substances
and which mostly mixtures?
column A is mostly pure substances and column B is mostly mixtures
column A is mostly mixtures and column B is mostly pure substances
Which substances are in the wrong column?
milk, graphite, raisin bran, gold
185. Which of the flasks below
will contain a mixture when all the hydrogen reacts with oxygen to give
Flask A, Flask B
For the amino acid glycine (H2N-CH2-CO2H),
the pKa of the -NH3+ group is about 10 and pKa of the -CO2H
group is about 2. At pH 0, what form of these groups is primarily present?
NH3+ and CO2H, NH3+ and CO2-,
NH2 and CO2H, NH2 and CO2-
The pKa of the weak acid, HF, is about 3. The pKb of the weak base F- is
-11, 3, 11, 1
The molecule shown below contains which functional groups?
amide, amine, alcohol
ester, amide, ether
ester, amine, ether
carboxylic acid, amide, alcohol
How many hydrogens are present in the structure?
8, 9, 10, 11
Which particle is emitted in the following nuclear reaction?
A, B, C
What is the formula of bis(ethylenediamine)dichlorocobalt (III)?
A, B, C
215. Water droplets were recently
made to perform the astonishing feat of climbing uphill against gravity
on a coated microscope slide. To make this process occur, the slide would
have to be coated in which of the following ways?
A. Uniformly coated with a polar film
B. Uniformly coated with a nonpolar film
C. Coated with a film that gradually increased in polarity from the
bottom of the slide to the top
D. Coated with a film that gradually decreased in polarity from the bottom
of the slide to the top
(Adapted from M. K. Chaudhury and G. M. Whitesides, Science, 256,
227. Take a square refrigerator magnet and cut off a thin strip from both
the horizontal and vertical edges. Place one of the thin magnetic strips
on the back of the large magnet as shown below and pull gently vertically
and then horizontally. Now try the other magnetic strip.
Which is the best representation of the magnetic field of the large magnet,
where N represents the north pole and S the south pole?
A, B, C
Ibuprofen is an anti-inflammatory drug also used as an aspirin substitute.
To what family of organic compounds does ibuprofen belong?
What alkyl group is attached to the para position of the benzene ring of
the ibuprofen molecule?
232. Procaine, a local anesthetic whose hydrochloride
salt is Novocain, has the following structure:
Identify the functional groups:
A. ester or amide
B. primary, secondary, tertiary amine
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