Chem 238 Lab Final Test Questions with 100%
Correct Answers
in a synthesis of 4-methylcyclohexane by dehydration of cyclohexanol (see th equation
given below), you start with 0.22 grams of the alcohol. the molecular weight of 4-
methylcyclohexanol is 114.19g/mo. how many molecules is this?
1160000000000000000000 (19 zeros)
in the aldol condensation reaction shown below, is the water a by-product or a side-
product?
by product
purification of a reaction product by extraction can be done in a couple of different
ways.
a) a liquid phase can be added that will extract the pure product from a mixture leaving
the impurities behind
b) a liquid phase can be added that will extract the impurities from a mixture (leaving
the pure product behind)
shown below is a schematic representation of a reaction with water. the alkene is the
desired product.
will extraction with water (aqueous extraction) extract the product from the mixture or
ill it extract the undesired by-products and other impurities from the mixture?
aqueous extraction extracts undesired by-product and impurities from the mixture
there are many selective oxidizing reagants that are often not covered in a lecture
course. one of these is potassium permanganate, KMnO4. You do not need to know how
potassium permanganate works in order to answer this question. shown below is
, oxidiation of an alcohol with potassium permanganate. there are two possible products,
A and B. Using the infrared spectrum of the actual product provided below, decide
whether the product is A or B.
the product is B (benzene to double bond O to OH)
the aldol reaction shown below is performed by stirring at room temperature. the
product anisalacetophenone crystallizes out of the reaction mixtures at room
temperature. what are the two major intermolecular forces that are responsible for
holding the molecules of the product together in the crystal?
hydrogen bonding and dipole dipole
shown below is an Aldol Condensation reaction. Which of the following reactant is
consistent with the following IR spectrum? A or B?
product B
Shown below is a synthesis of cyclohexane from cyclohexanol. which of the provided
infrared spectra corresponds to the alkene product, A,B,C, or D?
C
which of the solvents below are best characterized as polar aprotic?
(options: acetic acid, carbon tetrachloride, toluene, acetone, acetontrile, hexane, ethyl
acetate, methanol)
acetone, acetontrile, and ethyl acetate
which of the solvents below are best characterized as polar protic?
(options: acetic acid, carbon tetrachloride, toluene, acetone, acetontrile, hexane, ethyl
acetate, methanol)
Correct Answers
in a synthesis of 4-methylcyclohexane by dehydration of cyclohexanol (see th equation
given below), you start with 0.22 grams of the alcohol. the molecular weight of 4-
methylcyclohexanol is 114.19g/mo. how many molecules is this?
1160000000000000000000 (19 zeros)
in the aldol condensation reaction shown below, is the water a by-product or a side-
product?
by product
purification of a reaction product by extraction can be done in a couple of different
ways.
a) a liquid phase can be added that will extract the pure product from a mixture leaving
the impurities behind
b) a liquid phase can be added that will extract the impurities from a mixture (leaving
the pure product behind)
shown below is a schematic representation of a reaction with water. the alkene is the
desired product.
will extraction with water (aqueous extraction) extract the product from the mixture or
ill it extract the undesired by-products and other impurities from the mixture?
aqueous extraction extracts undesired by-product and impurities from the mixture
there are many selective oxidizing reagants that are often not covered in a lecture
course. one of these is potassium permanganate, KMnO4. You do not need to know how
potassium permanganate works in order to answer this question. shown below is
, oxidiation of an alcohol with potassium permanganate. there are two possible products,
A and B. Using the infrared spectrum of the actual product provided below, decide
whether the product is A or B.
the product is B (benzene to double bond O to OH)
the aldol reaction shown below is performed by stirring at room temperature. the
product anisalacetophenone crystallizes out of the reaction mixtures at room
temperature. what are the two major intermolecular forces that are responsible for
holding the molecules of the product together in the crystal?
hydrogen bonding and dipole dipole
shown below is an Aldol Condensation reaction. Which of the following reactant is
consistent with the following IR spectrum? A or B?
product B
Shown below is a synthesis of cyclohexane from cyclohexanol. which of the provided
infrared spectra corresponds to the alkene product, A,B,C, or D?
C
which of the solvents below are best characterized as polar aprotic?
(options: acetic acid, carbon tetrachloride, toluene, acetone, acetontrile, hexane, ethyl
acetate, methanol)
acetone, acetontrile, and ethyl acetate
which of the solvents below are best characterized as polar protic?
(options: acetic acid, carbon tetrachloride, toluene, acetone, acetontrile, hexane, ethyl
acetate, methanol)
