Chem Final
Which of the following could NOT be the temperature of a solid
-2K
How many meters are in 10.0 cm
0.100
A tablet contains 325.0 mg of the active ingredient. This mass may also be expressed as:
0.3250 g
How many kilometers are in 800 m
0.8
The results of an experiment are easiest to interpret when the experiment has________ variables
1
A solution with pH of 3 has a hydronium ion concentration of
10^-3 mol/L
When 32g of sulfur reacts with 48g of oxygen, 80g of sulfur trioxide is produced. If 16g of sulfur and 100g of oxygen are placed into a sealed container and are allowed to react, what is the mass of the material in the container after the reaction is completed
116g
Given: 2 g of sulfur will react with 3 g of oxygen to produce 5 g of sulfur trioxide. If 54 g of sulfur and 100g of oxygen are placed into a sealed container and are allowed to react, how much sulfur dioxide will be produced
135 g
A student working in the laboratory needs 200.0 g of a liquid chemical whose density is .690g/cm3. What volume of this liquid should she/he measure?
290 cm3
If the concentration of a dilute solution of nitric acid is .0001 M, what is the pH of that solution
4
The boiling point of a liquid is 178C. What us this temperature on the Kelvin scale?
451 K
When added to a sealed flask and heated , 6.0g of carbon and 16.0g of oxygen react to form 22.0g of carbon dioxide. How much carbon dioxide is formed when 24.0g of carbon is reacted with 100.0g of oxygen?
88.0 g
The species represented by CO is
A molecule made up of carbon and oxygen
Lemon Juice is...
Acidic
A scientific hypothesis is
All of the above Explanatory, predictive, testable
Joe conducts an experiment to test the effectiveness of a new drug for cancer. Which of the following variables would be easiest to control?
Amount of drug administered
What is the chemical symbol for gold
Au
Which of the following represents an compound
CO2
The Ancient Greek philosophers were probably the first to consider the behavior of matter in an organized way. What is the major distinction between "Greek philosophers" and the "modern scientist"
Experimentation
An oxidation reaction often occurs without a corresponding reduction reaction
F
A compound with polar bonds must be polar
False
A metal oxide will form an acid when when it is dissolved in water
False
Anions migrate toward the cathode.
False
Aristotle's idea that matter is continuous is still considered to be correct
False
Corrosion of batteries is caused by the reduction of metals
False
In an electrochemical cell, oxidation takes place at the cathode
False
Matter is a measure of the amount of mass in an object
False
Mendeleev was the first person to attempt to arrange the elements in a systematic order
False
Naturally occurring reactions of oxygen (O2) are always desirable.
False
Organic foods do not contain chemicals
False
Substance A contains 80% carbon and 20% hydrogen. Substance B contains 83% carbon and 17% hydrogen. A and B are the same substance
False
The substances in a heterogeneous mixture retain their chemical identity, but those in a homogenous mixture do not
False
There is no difference between the hazard posed by an element when it is in a compound or by itself
False
Water has a density of 1.00g/ml. If you put an object that has the same density of .79g/ml into water, it will sink to the bottom
False
What is the chemical symbol for iron
Fe
Which of the following CANNOT be the chemical symbol for an element
H2
Sulfuric Acid is the leading chemical produced and used industrially. What is the formula for sulfuric acid?
H2SO4
Which one of the following is NOT an example of Green Chemistry
Hydrocarbons containing only Carbon and H atoms are used as a fuel source.
A molecule
Is the smallest characteristic part of a compound
In the SI system of measurement the unit of mass is the
Kilogram
What is the name of the element with the symbol Hg
Mercury
Which of these does NOT involve a chemical change
Mercury is used in barometers because it has a high density
In the SI system of measure the, the unit of length is the
Meter
Tangible items of pictures used by scientists to represent invisible processes are called
Models
Which of the following statements about atoms is NOT true
No atoms have been synthesized by scientists.
A hydrogen ion, H+ is the same as
Proton
Which of the following represents an element
Se
What is the name of the element with the symbol Ag
Silver
The evaluation of societal risk includes all of the following components of individual risk plus
The number of people affected by the incident
Which of the following was not a result of alchemy
The philosopher's stone was successfully used to change base metals, such as lead, into gold.
Which of the following is not an outcome for companies that use green chemistry
They no longer have to follow federal pollution guidelines
A molecule is a group of atoms that are chemically bonded together.
True
All clothing contains chemicals
True
An example of a chemical change is browning of meat
True
An example of a physical change is a gas becoming a liquid
True
An orbital is a region in space in which there is a high probability of finding an electro
True
Antacids are basic compounds
True
Chemistry affects every aspect of our daily lives
True
During a chemical reaction, matter can neither be created nor destroyed
True
Heat will always glow from a warmer object to a cooler object
True
If a compound is a base according to Arrhenius definition, it will also be a base according to the Bronsted Lowry definition.
True
In Food Chemistry, reducing agents are sometimes referred to as antioxidants.
True
Mass is a measure of the amount of matter in an ovject
True
NO is a free radical.
True
Rainwater has a pH below 7 because raindrops absorb CO2 which can react with with water to form Carbonic Acid
True
Science does not prove a theory of hypothesis to be true. It can only prove something false
True
The destructive power generated by an explosive mixture results from the rapid expansion of gaseous products
True
The technology of smelly metals into ores was preformed long before the science of metallurgy evolved
True
A nonmetal oxide is called a
acidic compound
Which of the following does NOT involve chemistry
all of the above Creating materials for computers Glycolysis Burning of a forest
A chemist employed by an airplane manufacturer investigates new adhesives for the purpose of building airplanes without rivets. She is engaged in
applied research
A chemical change always involves a change in the _________ of matter
composition
One of the hallmarks of science is the ability to think ________.
critically
A salt that can conduct electricity when it is dissolved in water is a(n)
electrolyte
All redox reactions occur with the transfer of
electrons
Scientific results must be verified by
further experiment
A solution is another name for
homogeneous mixture
H3O+ is the
hydronium ion
A gas is characterized by a(n)
indefinite shape and indefinite volume
When doing a risk-benefit analysis and determining DQ, which situation is often the most difficult to evaluate from both an individual and societal perspective?
large benefit and high risk
The ability to recycle aluminum (or glass, or plastic) is ultimately an illustration of
law of conservation of mass
Methapyrilene, once an active ingredient in certain over-the-counter sleeping pills, was found to be a potent carcinogen (a substance that causes cancer). The pills were also found to be about as effective as placebos in promoting sleep. The desirability quotient (DQ) for methapyrilene is
low
Mass is a better measure of the amount of matter than weight is because
mass is independent of location
Vinegar is composed of approximately 5% acetic acid and 95% water. Which one of the following is the best classification of vinegar?
mixture
In a reactions, the substance undergoing reduction serves as the
oxidizing agent
A conjugate acid-base pair differ by one
proton
Which of the following is a definition of reduction
reduction is the gain of hydrogen
Green chemists reduce the risk associated with the manufacture of a product by doing all of the following EXCEPT
requiring workers to use protective equipment
A buffer
resists change in pH, is made up of a weak acid and conjugate base, weak base and conjugate acid. (All of The Above)
When an aqueous solution containing hydrochloric acid is just neutralized with an aqueous solution containing sodium hydroxide, the solution would taste
salty
Which of these is a chemical change
silkworms convert mulberry leaves into silk
The physical state that retains both shape and volume is
solid
______________ chemistry is designed to meet the needs of the present generation without compromising the needs of future generations
sustainable
Archaeological evidence indicates that ancient Egyptians were brewing beer and other fermented beverages over 4000 years ago. In the mid 19th century, french scientist Louis Pasteur discovered and explained the source of fermentation using yeast. This example illustrates that
technological knowledge may come before scientific knowledge
scientific hypothesis is
tentative
Chemist A claims that a new compound will inhibit the growth of a virulent strain of bacteria. When Chemist B from a different laboratory tests the compound against the same bacterial strain, the bacteria grow at their normal rate. Which of the following statements best describes what has happened?
the claim is incorrect, because the test has not been replicated
Bronsted-Lowry useful broad view of reactions between acids and bases involve the
transfer of protons
Saccharin is used in some artificial sweeteners. Saccharin has been shown to be a very weak carcinogen (a substance that causes cancer) in animal tests, but there is little evidence of carcinogenicity in humans. Studies have also shown that artificial sweeteners provide little benefit to those who want to lose weight. The DQ for saccharin is:
uncertain
Give an example of an amphiprotic compound
water
A solution of a toilet bowl cleaner has a pH of 9. The solution is
weakly basic