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