Chemistry 021 Term Test # 1: Wednesday, November 5, 2003
1)
Which of the following statements concerning MIXTURES is correct ?
A) They are combinations which can only be separated by chemical processes.**
B) They are combinations that cannot be separated by physical processes.
C) They are a combination of two or more substances mixed in equal proportion.
D) They are a combination of two or mores substances mixed in any proportion.
2)
Which of the following statements concerning gases is correct ?
A) Gases do not have mass.
B) Gases will assume the volume of their container.
C) Gas molecules are usually very close together.**
D) Gases do not have a measured density.
3)
In which of the following scenarios would a vapour pressure be exerted ?
A) A closed container**
B) An open container
C) A container with a screen on the top
D) A container with a hole on the side
4)
Which of the following is true for chemical equations ?
A) The number of reactant molecules is equal to the number of product atoms.
B) They summarize the interchange of molecules.
C) They summarize interchanges of gases.
D) They summarize interchange of atoms.**
5)
Candles often produce a black residue called “soot”. This is caused by......
A) Complete oxidation of the candle.
B) Incomplete combustion of the candle.**
C) A dirty wick on the candle.
D) Melting of the candle.
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Chemistry 021 Term Test # 1: Wednesday, November 5, 2003
6)
The
A)
B)
C)
D)
“model” of the atom that we studied consists of:
Electrons embedded in a sphere about the nucleus.
Protons embedded in the nucleus with electrons and neutrons moving around it.
Neutrons embedded in the nucleus with protons and electrons orbiting it.
Electrons orbiting the nucleus, which contains protons and neutrons.**
7)
In an atom, consider the electrons which are closest to the nucleus. They are.....
A) The easiest electrons to remove from the atom.
B) At the same level of energy as all the other electrons in the atom.
C) Responsible for the chemical properties of the atom.
D) The most difficult electrons to remove from the atom.**
8)
Electronegativity may be defined as......
A) An atoms ability to lose electrons.
B) An atoms ability to attract shared electron pairs when forming a covalent
bond.**
C) An atoms ability to attract electrons from a neighboring molecule.
D) An atoms ability to form solutions which conduct electricity.
9)
Which of the following statements concerning all carbon atoms is incorrect ?
A) Each carbon atom always forms a total of 4 bonds.
B) When forming bonds, carbon atoms always share all the electrons in the outer
shell.
C) Each carbon atom in a compound has 8 electrons in the outer shell.
D) Unbonded carbon atoms have 8 electrons in their outermost shell.**
10) Isomers may be defined as:
A) Molecules which have similar structures, but contain some different atoms.
B) Molecules which have alternating double bonds.
C) Molecules which must contain double bonds.
D) Molecules which have the same numbers of atoms, but different structures.**
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Chemistry 021 Term Test # 1: Wednesday, November 5, 2003
11) The
A)
B)
C)
D)
separation of petroleum utilizes the process of distillation, which is based on...
The different densities of the compounds in petroleum.
The different boiling points of the compounds in petroleum.**
The different octane ratings of the compounds in petroleum.
The different solubilities of the compounds in petroleum.
12) Because of the high volatility of certain compounds in gasoline, different
formulations of gasoline are produced based on......
A) The cost of production
B) The availability of the compounds involved
C) The season in which the gasoline is to be used**
D) Their contribution to air pollution
13) Which of the following statements concerning coal is incorrect ?
A) Coal is the most abundant fossil fuel.
B) The burning of coal produces compounds which contribute to air pollution.
C) The principle use of coal today is for burning in fireplaces.**
D) The carbon content of coal increases with the age of the coal.
14) The
A)
B)
C)
D)
definition of a “plastic” is......
A material that is a polymer
A material that is a hydrocarbon
A material that is pliable
A material that can be molded**
15) “Plasticizers” are
A) Substances added to polymers to make them into plastics
B) Substances added to polymers to increase flexibility**
C) Substances added to polymers to make them highly coloured
D) Substances added to monomers to make them polymerize
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Chemistry 021 Term Test # 1: Wednesday, November 5, 2003
16) Polymers that are produced to conduct electricity have which of the following
molecular structures ?
A) Alternating double and single bonds**
B) Alternating triple and single bonds
C) Alternating double and triple bonds
D) Continuous double bonds
17) Diamond is the hardest substance known due to its unique structure, which consists
of....
A) Long linear chains of carbon atoms
B) Large sheets of six membered carbon rings
C) A network of tetrahedrally bonded carbon atoms**
D) A sphere containing sixty carbon atoms
18) The
A)
B)
C)
D)
expression of LD50 represents....
50 % of the toxic substance
The minimum dose that is lethal for 50 proof alcohol
The minimum dose for 50% body weight
The minimum dose that is lethal to 50% of the population**
19) As the length of the carbon chain in an alcohol increases....
A) The solubility decreases.**
B) The alcohol becomes sweeter to taste
C) The boiling point decreases.
D) The proof value of the alcohol increases
20) Drinking too much alcohol can result in a “hangover”, which is caused by the
formation of....
A) Carboxylic acids
B) Aldehydes**
C) Ketones
D) Esters
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