Chem 1st exam
Identify the single most effective strategy to reduce carbon dioxide emissions.
Develop alternate energy sources that do not rely on fossil fuels
Both the Clinton and Bush (the younger) administrations have been unwilling to sign the Kyoto Protocol. What has been their primary objection to the treaty?
Developing countries are not required to control greenhouse gas emissions
How is heat energy used to generate electricity in a modern power plant?
Heat boils water to make steam, which drives a turbine
Sunscreens __________________ thereby protecting your skin from some of the sun's radiation
absorb UV-A and UV-B radiation
The energy needed to initiate a chemical reaction is called the
activation energy
Chlorofluorocarbons rise to the stratosphere and
after interacting with UV energy, become free radicals, which destroy ozone
Which element has the same number of valence electrons as boron? A. Li B. As C. Al D. P
al
Global warming will have impacts on A. human health B. natural ecological systems C. socioeconomic systems D. all of the above
all of the above
In the past century A. CO2 concentrations have increased by about 30% B. the average temperature of the planet has increased in about 0.6 ˚C C. Global precipitation over land has increased 1% D. all of the above
all of the above
Which of the following is classified as a "greenhouse gas"? A. carbon dioxide B. nitrous oxide C. methane D. all of the following
all of the following
Ozone (O3) and oxygen (O2) are
allotropes
When potassium (K) and bromine (Br) are combined, they most likely form
an ionic bond (K+Br-)
The number of protons in an atom is called the
atomic number
The modern periodic law of the elements states that the properties of the elements are periodic functions of
atomic numbers
The primary element in coal is
carbon
The most biologically important of the minor components of dry air is
carbon dioxide
When CFCs absorb highly energetic radiation they produce chlorine atoms (Cl) that
catalyze the decomposition of ozone
When coal burns
chemical energy is converted to heat energy
The first law of thermodynamics deals with
conservation of energy
The heating of large hydrocarbon compounds in the absence of oxygen with a catalyst is called
cracking
Which will absorb more UV radiation A. A 1 km layer of air with an average ozone concentration of 1.0 ppm. B. A 3 km layer of air with an average ozone concentration of 0.5 ppm. C. A 1 km layer of air with an average ozone concentration of 2.0 ppm. D. A 2 km layer of air with an average ozone concentration of 1.5 ppm
d
When an ozone molecule absorbs high energy radiation, it breaks up into
diatomic oxygen and an oxygen atom.
Carbon dioxide is best described as
essential for life on earth
The term "greenhouse effect" is derived from the fact that
greenhouse gases act like the glass in a greenhouse
The main components of petroleum are
hydrocarbons
Catalytic cracking of heavier fractions is a process used to
increase the yield of gasoline from petroleum
Which form of electromagnetic radiation from the Sun has the lowest energy and therefore the least potential for damage to biological systems?
infrared
Greenhouse gases raise the Earth's temperature by absorbing
infrared radiation
isomer v isotope
isomer has the same composition but a different shape/connectivity. isotopes have a different number of neutrons than the parent atom
Sodium ions (Na+) differ from sodium atoms in that the ions have one
less electron than the atom
The major component of natural gas is
methane
A compound that has replaced tetraethyllead as an octane booster is
methyl tert-butyl ether
If drops of water are subdivided to the ultimately smallest drops possible, what is the smallest particle of water that retains the chemical and physical properties of water?
molecule
If two electrons were removed from the outermost energy level of a magnesium atom, the new electron configuration would resemble that of what element?
ne
The most abundant component of dry air is
nitrogen
What distinguishes one element from another
number of protons
Elements in the same period (row) of the Periodic Table have
numbers, mass etc all different
The second most abundant component of dry air is
oxygen
What metal, when added as a compound, increases octane rating of gasoline
pb
With respect to reactivity at normal temperatures, nitrogen is best classified as
relatively unreactive
Elements in the same group (column) generally have
similar properties
When only one pair of shared electrons is involved in a covalent bond, the linkage is called
single bond
_________ is a measure of the heat required to change the temperature of a substance
specific heat
The protective Ozone layer is found in what region of the atmosphere?
stratosphere
Past Earth's temperatures are estimated from
the isotopic ratio 2H/1H in ice cores in Antarctica
The Montreal protocol is a
treaty to reduce the amount of CFCs produced in the world
Ozone protects the surface of the Earth from
ultraviolet radiation
DNA, the genetic material of living organisms, is damaged by light in the
ultraviolet region, especially below a wavelength of 320 nm
In terms of reactivity, ozone is best classified as
very reactive
Infrared radiation excites
vibrational transitions in molecules
. List four other greenhouse gases, in addition to carbon dioxide, and arrange them in order of increasing greenhouse factor. Indicate the source of each of these gases.
water vapor, methane, nitrous oxide, ozone
The combustion process for an effective fossil fuel must have an activation energy that is neither too high nor too low. Why is it problematic if the combustion has a very low activation energy?
The fuel will ignite too easily and be hazardous.
Determine the geometry of PH3
. trigonal pyramidal
In order to make useful predictions, which factors must be accounted for by climatic models?
.Combustion of fossil fuels
The nuclear charge of a sodium atom (Na) is
11+
It is estimated that 750 Gt of carbon resides in the atmosphere and that another 5,000 Gt is stored in the earth as fossil fuels. If 10% of the total fossil fuel carbon is combusted and released into the atmosphere, what would be the percentage increase for carbon in the atmosphere? (1 Gigaton (Gt) =
67%
A gasoline with an octane rating of 90 would give the same performance in a standard test engine as a mixture of
90% isooctane and 10% heptane
Which element is a noble gas? A. B B. Ge C. Ar D. K
Ar
Which is a correct description of the organization of subatomic particles in atoms? A. Protons and electrons are tightly packed into a small nucleus. Neutrons occupy the space outside the nucleus. B. Protons and neutrons are tightly packed into a small nucleus. Electrons occupy the space outside the nucleus. C. Neutrons and electrons are tightly packed into a small nucleus. Protons occupy the space outside of the nucleus. D. Electrons are tightly packed into a small nucleus. Protons and neutrons occupy the space outside of the nucleus.
B. Protons and neutrons are tightly packed into a small nucleus. Electrons occupy the space outside the nucleus.
Even if all CFC production could be stopped today, the ozone depletion problem in the stratosphere would continue for many years because
CFCs are widespread and very stable in the troposphere
The main product in the combustion of coal is
CO2