Midterm Exan Flashcards
The smallest chemical unit of matter
Atom
Two or more atoms linked together to make a substance with unique properties
Molecule
The quantity of a substance within a certain volume
Concentration
Sulfur is a yellow powder that is composed of sulfur atoms. Sulfur dioxide is a colorless, poisonous gas that contains sulfur atoms. Is sulfur dioxide composed of atoms or molecules?
Sulfur dioxide is composed of molecules
While looking at historical grave markers, you find a statuette that is blue-green in color. In order to read the inscription, you scrub the surface of the statuette, and the blue-green color comes off as a fine powder. What color is the statue underneath?
The statue will have a copper color underneath the green powder
Which picture represents a bunch of atoms? Which represents a bunch of molecules?
Picture A represents a bunch of molecules, whereas picture B is a representation of a bunch of atoms
You are reading a scientist’s notes and you notice a measurement that is listed as “12.3 kilograms.” Does this measurement represent length, mass, or volume?
This is a measurement of mass
What metric prefix means “1,000”?
kilo
How many centimeters are in 1.6 meters?
160 cm
An object’s volume is 0.12 kL. What is its volume in liters?
120 L
A rock has a mass of 45.1 kg. What is its mass in slugs? (1 slug = 14.59 kg)
3.09 slugs
Ammonia is the active ingredient in many household cleaners. Suppose I were to make up two buckets of cleaner. In the first, I take 5 cups of ammonia and add them to 45 cups of water. In the second, I will take 5 cups of ammonia and add them to 30 cups of water. Which bucket contains the most powerful cleaner?
The second bucket has the more powerful cleaner
The moisture content of air
Humidity
The mass of water vapor contained in a certain volume of air
Absolute humidity
The ratio of the mass of water vapor in the air at a given temperature to the maximum mass of water vapor the air could hold at that temperature, expressed as a percentage.
Relative humidity
The process by which certain gases (principally water vapor, carbon dioxide, and methane) trap heat that radiates from earth
Greenhouse effect
The number of molecules (or atoms) of a substance in a mixture for every 1 million molecules (or atoms) in that mixture
Parts per million
When does water evaporate more slowly – under conditions of high humidity or low humidity?
Water evaporates slowly under conditions of high humidity
Will sweating help cool you down when the humidity is 100%?
No, sweating will not cool you down
What gas makes up the majority of the air we inhale?
Nitrogen
What gas makes up the majority of the air we exhale?
Nitrogen
A chemist is monitoring the rate at which a certain substance burns. The chemist burns the substance in a fireplace that uses the room’s air supply. The chemist then repeats the experiment, this time in a chamber whose air mixture is 50% oxygen and 50% nitrogen. In which trial will the substance burn the fastest?
The substance will burn the fastest in the second trial
Why is it important to have ozone in earth’s air?
Ozone blocks the ultraviolet light from the sun
For good health, should we increase or decrease the concentration of ground-level ozone in the air?
Ground-level ozone concentrations should be decreased
Has the average temperature of the earth increased significantly in the past 80 years?
No
Convert 1% into ppm.
10,000 ppm
The concentration of nitrogen oxides in the air today is about 0.018 ppm. What is that in percent?
0.0000018 %
What pollutant concentration was decreased by the mandate of catalytic converters?
Catalytic converters reduced the concentration of carbon monoxide
The mass of air surrounding a planet
Atmosphere
An instrument used to measure atmospheric pressure
Barometer
The lower layer of earth’s atmosphere, which exists from ground level to roughly 80 kilometers (50 miles) above sea level
Homosphere
The upper layer of earth’s atmosphere, which exists higher than roughly 80 kilometers (50 miles) above sea level
Heterosphere
Narrow bands of high-speed winds that circle the earth, blowing from west to east
Jet streams
Energy that is transferred as a consequence of temperature differences
Heat
A measure of the energy of random motion in a substance’s molecules
Temperature
If you want to study weather, which region of the atmosphere would you study?
You would study the troposphere
If you want to study the ozone layer, which region of the atmosphere would you study?
You would study the stratosphere
If a sample of air is predominately oxygen, did it most likely come from the homosphere or the heterosphere?
It must have come from the heterosphere
Which regions of the atmosphere are in the homosphere?
The troposphere, stratosphere, and mesosphere
Which regions of the atmosphere are in the heterosphere?
The thermosphere and exosphere are in the heterosphere
A barometer develops a leak in the column which is supposed to be free of air. As air seeps into the column, what will happen to the height of the liquid in that column?
The height of the column will decrease
In what region(s) of the homosphere does temperature increase with increasing altitude?
stratosphere
Why is the “ozone hole” a seasonal phenomenon that exists mostly at the South Pole?
The “ozone hole” is a seasonal phenomenon located only at the South Pole because ozone cannot be depleted by CFCs without the aid of the Polar Vortex
We all know that ice melts because of heat. Why is it correct to say that ice also freezes because of heat?
Heat is energy that is being transferred. To freeze water, energy must be transferred from the water to the surroundings
If you were able to measure the speed of the molecules in the air while you were traveling up through the troposphere, would the speed of the molecules increase, decrease, or stay the same as your altitude increased?
decrease
The use of electricity to break a molecule down into smaller units
Electrolysis
A molecule that has slight positive and negative charges due to an imbalance in the way electrons are shared
Polar molecule
A liquid substance capable of dissolving other substances
Solvent
A substance that is dissolved in a solvent
Solute
The phenomenon that occurs when individual molecules are so strongly attracted to each other that they tend to stay together, even when exposed to tension
Cohesion
Water that has certain dissolved ions in it – predominately calcium and magnesium ions
Hard water
What is the chemical formula for water?
H2O
Some metals tend to absorb oxygen but not hydrogen. Suppose such a metal was covering the battery in an electrolysis experiment like Experiment 4.1. Which is the more likely erroneous result the experiment would yield for the chemical formula of water: HO2 or H4O?
H4O would be the more likely erroneous result
Why is water a liquid at room temperature when all other chemically similar substances are gases at room temperature?
Hydrogen bonding
Carbon dioxide (CO2) is one of the gases that we exhale when we breathe. Carbon monoxide (CO) is a poisonous gas associated with burning things under conditions of low oxygen. How many atoms are in one molecule of CO2? How many atoms are in one molecule of CO?
There are three atoms in a carbon dioxide molecule and two atoms in a carbon monoxide molecule
An important component of gasoline is octane, which is composed of molecules that have eight carbon atoms (C) and eighteen hydrogen atoms (H). What is the chemical formula of octane?
C8H18
Why are water molecules polar?
Water molecules are polar because both the oxygen atoms and the hydrogen atoms are fighting over the electrons they are supposed to be sharing. Oxygen can pull on those electrons harder, so it gets more than its fair share of electrons, making it slightly negative. Since the hydrogen atoms get less than their fair share of electrons, they end up slightly positive
If a substance does not dissolve in water, is it most likely ionic, polar, or nonpolar?
nonpolar
If a substance dissolves in water, will it dissolve in vegetable oil, a nonpolar substance?
It will not dissolve in vegetable oil
Is hard water the result of a city’s water treatment process?
No
Evaporation of water from plants
Transpiration
The process by which a gas turns into a liquid
Condensation
The average time a given particle will stay in a given system
Residence time
The process by which water moves downward in the soil, toward the water table
Percolation
The cooling of a gas that happens when the gas expands with no way of getting more energy
Adiabatic cooling
Where does the majority of earth’s water reside?
oceans
What is the largest source of liquid freshwater on the planet?
Groundwater
What water source is a molecule of water in once it has gone through transpiration?
atmosphere
Water was in the ocean and is now in a cloud. What two hydrologic cycle processes happened in order to make that transfer?
Evaporation, condensation
Where is the residence time longer: in the ocean or in a fast-moving stream?
the ocean
If a lake has no means of getting rid of water except evaporation, does it contain saltwater or freshwater?
It contains saltwater
What do the oceans tell us about the age of the earth?
They tell us that the earth can’t be billions of years old
An enormous amount of ocean water in the polar region freezes. Does it form an iceberg? Why or why not?
It does not form an iceberg. Icebergs are freshwater and come from glaciers
What process in the hydrologic cycle is responsible for making glaciers?
Precipitation
What causes the temperature change that allows for condensation, which makes most clouds?
Adiabatic cooling
If a sample of gas is compressed and nothing else is allowed to change, what will happen to the temperature of the gas?
The temperature will increase
If there is a lot more rain than normal in an area over an extensive length of time, what happens to the depth of the water table?
The depth of the water table will decrease
Why is groundwater pollution so hard to trace back to its original source?
The nature of groundwater flow makes it such that a lake can be polluted by groundwater that originally soaked into the soil hundreds of miles away
Rock formed when chemical reactions cement sediments together, hardening them
Sedimentary rock
Rock that behaves like something between a liquid and a solid
Plastic rock
The boundary between two sections of rock that can move relative to one another
Fault
The point on the surface of the earth directly above an earthquake’s focus
Epicenter
Label the sections (a-e) of the earth shown in the figure:
a. crust
b. asthenosphere c. mantle
d. outer core
e. inner core
What have scientists observed in order to learn about earth’s interior?
seismic waves
Between what two regions of the earth can you find the Moho?
crust, mantle
What causes the earth’s magnetic field?
Electrical flow in the core
What two theories attempt to explain the earth’s magnetic field? Which theory is the most scientifically valid?
The dynamo theory and the rapid- decay theory, The rapid-decay theory is more scientifically valid
What major benefit do we derive from the earth’s magnetic field?
The earth’s magnetic field blocks cosmic rays from the sun
In a survey of the deep ocean, sonar measurements detect a deep trench on the bottom that runs as far as the instruments detect. What is the most likely cause of the trench?
The trench is probably the site where one plate interacts with another
The earthquake activity of two regions on earth is measured. The first region sits near the middle of one of the plates in the earth’s crust, while the other is very near a boundary between two plates. Which will (most likely) have the greatest earthquake activity?
The region nearest the plate boundary should have more earthquakes
Many powerful earthquakes are followed later by less-powerful earthquakes called “aftershocks.” If an earthquake measures 6 on the Richter scale and is followed by an aftershock that measures 4, how many times more energy was released in the original earthquake as compared to the aftershock?
1,024 times more energetic than the aftershock
If a region of the earth has a lot of volcanic activity, what kinds of mountains do you expect to find there?
You expect to find both volcanic mountains and domed mountains
Many scientists think that at one time, all the continents might have fit together to form a supercontinent. What is the name of this supercontinent?
Pangaea
The point at which the earth is farthest from the sun
Aphelion
The point at which the earth is closest to the sun
Perihelion
The way in which the rotation of the earth bends the path of winds, sea currents, and objects that fly through different latitudes
Coriolis effect
A large body of air with relatively uniform pressure, temperature, and humidity
Air mass
A boundary between two air masses
Weather front
Identify the clouds in the following pictures:
a. stratus (stratonimbus or nimbostratus is okay also) b. cirrus c. cumulus
Of the 3 main factors that influence weather, which is mostly responsible for winds?
uneven distribution of thermal energy
What are dark cumulus clouds called?
cumulonimbus
If an area receives a large amount of insolation, is it likely to be warm or cold?
it is warm
In the Northern Hemisphere, are the day lengths greater than or less than 12 hours between the winter solstice and the spring equinox? Are the day lengths increasing or decreasing during that time?
increasing, less than 12 hours
Why is the Northern Hemisphere in winter when the earth is closest to the sun?
The Northern Hemisphere is pointed away from the sun
Suppose you are at the equator and want to fire a missile at a target due north of your location. Would you aim the missile north, northwest, or northeast in order to ensure it hits the intended target?
northwest
Without two specific factors, the global wind patterns would be simple. They would blow from the poles to the equator. What two factors shape the global winds into the complex patterns that we actually see?
The change in temperature caused by air changing latitude, the Coriolis effect
What causes the wind in a certain region to be different from what we expect based on the global patterns we see?
Local winds
An air mass is dry and warm. What kind of air mass is it?
continental tropical
You watch the sky as cirrus clouds form followed by stratus and nimbostratus clouds. Do you expect a violent rainstorm or a long, lighter rain?
long, lighter rain
A current of rising air
Updraft
A substance that does not conduct electricity very well
Insulator
The same cloud precipitates snow on a mountain and rain in the nearby valley. Does the Bergeron process or the collision-coalescence theory best describe the process causing precipitation from that cloud?
The Bergeron process
What is the dew point? What two factors influence it?
The dew point is the temperature at which water vapor condenses out of the air onto ground-level surfaces, humidity, pressure
A thunderstorm cell is raining, and there is no updraft. In what stage is the thunderstorm cell? Will there be hail at this point in the thunderstorm?
The thunderstorm is in its dissipation stage. No hail will exist
If the mature stage of a thunderstorm lasts for 30 minutes maximum, why can thunderstorms rain heavy sheets of rain for several hours?
These thunderstorms are made up of several cells
Why don’t you see lightning from nimbostratus clouds?
The charge imbalance that causes lightning starts in a cloud and cannot form unless the cloud is tall
What happens first in a lightning bolt: a return stroke or a stepped leader?
The stepped leader
How does lightning cause thunder?
Lightning causes thunder by heating up the air through which it passes
Is it possible for sheet lightning to strike a person?
Sheet lightning cannot strike a person
A tornado is in its organization stage. Has it touched the ground yet?
Yes, it has touched ground
What differentiates a tropical storm from a tropical disturbance?
Wind speed
Where is the calmest part of a hurricane?
eye
Is the atmospheric pressure in Houston, TX higher, lower, or equivalent to that in Atlanta, GA?
is equivalent
Is the atmospheric pressure in Chicago, IL higher, lower, or equivalent to that in New York, NY?
higher
What city listed on the map might have been experiencing thundershowers at the time this map was drawn
New York
What city listed on the map should expect warmer weather?
Houston
