Test 3
Chemical energy is converted directly into electrical energy in A. a battery. B. an electrical power plant. C. an electrolytic cell. D. an automobile's engine.
A. a battery.
Which is not a component of a fuel cell? A. a timer B. an anode C. a cathode D. an electrolyte
A. a timer
Which type of widely used battery is not rechargeable? A. alkaline B. lithium-ion C. lead-acid (storage batteries) D. nickel-cadmium (NiCad)
A. alkaline
In an electrochemical cell, the anode is A. the electrode at which oxidation takes place. B. the material used to connect the two half cells to each other. C. always used up before the cathode. D. never a metal.
A. the electrode at which oxidation takes place.
What is the primary determinant of the voltage developed by a battery? A. the nature of the materials in the reaction B. the age of the battery C. the overall size of the galvanic cells D. the size of the electrodes
A. the nature of the materials in the reaction
The VOLT is a common unit associated with electricity and it is a measure of A. The length of the cell B. The electric potential C. The amount of charge per second D. None of the above
B. The electric potential
Which functional groups are present in all proteins? A. amine ( NH2) groups only B. acid ( COOH) groups only C. amine and acid groups D. single and double bonds between carbon atoms
C. amine and acid groups
A polymer that is made from two different monomers is known as a A. dimer. B. dipolymer. C. copolymer. D. multimer.
C. copolymer.
In a galvanic cell, A. oxidation takes place at the cathode. B. electrolytes are added to carry electrons between electrodes. C. oxidation and reduction take place at the same time at different electrodes. D. electrical energy is used to reverse spontaneous chemical reactions.
C. oxidation and reduction take place at the same time at different electrodes.
Skin, hair, muscle, and enzymes are all made of protein, which is a natural polymer. Proteins are A. polyesters. B. polyethylenes. C. polyamides. D. polyalcohols.
C. polyamides.
In the lead-acid (storage) battery, (see picture) the cathode is the A. H2SO4 electrolyte. B. negative plates, lead/spongy lead. C. positive plates, lead/PbO2. D. casing enclosing the entire battery.
C. positive plates, lead/PbO2
Which is the cathode in this galvanic cell? (see picture) A. the solid zinc electrode B. the Zn2+(aq) ions in the 1 M solution C. the solid silver electrode D. the Ag+(aq) ions in the 1 M solution
C. the solid silver electrode
How many carbon atoms are present in this monomer? (see picture) A. 2 B. 3 C. 5 D. 8
D. 8
Which atoms are present in all proteins? A. C, H, O, N B. C, H, O, S C. C, H, O only D. C, H, N only
A. C, H, O, N
Glucose from corn is the source of some new bio-based polymer materials. Glucose also is the monomer in cellulose. Earlier in this text you encountered glucose in the chemical reaction of photosynthesis. What is photosynthesis and from what is glucose produced? A. It is the process that occurs when green plants use the energy of sunlight to produce glucose from carbon dioxide and water. B. It is a process to obtain table sugar C. It is a process to produce sunlight energy from carbon dioxide and water D. It is the process used by mammals to eat
A. It is the process that occurs when green plants use the energy of sunlight to produce glucose from carbon dioxide and water.
Which would be classified as a "natural" polymer? A. cellulose B. polystyrene C. polyester D. nylon
A. cellulose
Which raw material serves as the source for most polymers? A. crude oil B. natural gas C. minerals D. salts
A. crude oil
The regions of a polymer where the long polymer molecules are arranged neatly and tightly in a regular pattern is called the ________ region. A. crystalline B. amorphous C. condensed D. porous
A. crystalline
Polystyrene is used to make A. foam coffee cups and CD cases. B. garbage bags and CDs. C. shoes and garden hoses. D. cell phones and contact lenses.
A. foam coffee cups and CD cases.
In general, a modern hybrid vehicle is less polluting than a standard vehicle because it runs on both a A. gasoline engine and an electric motor run by a rechargeable battery. B. gasoline engine and a fuel cell. C. fuel cell and an electric motor run by a rechargeable battery. D. gasoline engine and a cleaner diesel engine.
A. gasoline engine and an electric motor run by a rechargeable battery.
Polystyrene is used to make Styrofoam® cups. For this usage, which property is most important? A. good insulator B. light weight C. white and opaque D. brittle
A. good insulator
This is the structure of propylene. Which of these represents the "head-to-tail, head-to-tail" arrangement of monomers in polypropylene? A. B. C. D.
B. Ch3H all the way
Which of these is vinyl chloride? A. B. C. D.
B. H & CL
This is a schematic representation of the two different forms of polyethylene. (see picture) Which of the following statements is true? A. I is HDPE and it has a lower melting point than II which is LDPE. B. I is HDPE and it has a higher melting point than II which is LDPE. C. I is LDPE and it has a lower melting point than II which is HDPE. D. I is LDPE and it has a higher melting point than II which is HDPE.
B. I is HDPE and it has a higher melting point than II which is LDPE.
Which is an amine group? A. OH B. NH2 C. COOH D. CNOH
B. NH2
Which structure represents a peptide bond? A. B. C. D.
B. O=C-N-
These are the densities of some common plastics: PET 1.38 to 1.39 g/mL; HDPE 0.95 to 0.97 g/mL; LDPE 0.90 to 0.91 g/mL. Based on these densities, which plastic/s will sink in an ethanol/water mixture that has a density of 0.94 g/mL? A. PET only B. PET and HDPE C. HDPE only D. LDPE only
B. PET and HDPE
Incineration of plastics can be used to generate energy. One of the "Big Six" plastics releases hydrochloric acid, HCl, when incinerated. Which one? A. LDPE B. PVC C. PET D. PS
B. PVC
Which is an oxidation half-reaction? A. 2 H2 + O2 → 2 H2O B. Zn → Zn2+ + 2 e¯ C. 2 HCl + Ba(OH)2 → 2 H2O + BaCl2 D. Cl2 + 2 e¯ → 2 Cl¯
B. Zn → Zn2+ + 2 e¯
The opposite of a galvanic cell is A. a battery. B. an electrolytic cell. C. a fuel cell. D. a photovoltaic (solar) cell.
B. an electrolytic cell.
The "Big Six" polymers are all classified as thermoplastics because they A. are all used as insulators. B. can be melted and shaped. C. are all crystalline. D. are all amorphous.
B. can be melted and shaped.
What do the letters HDPE represent? A. high definition polyethylene B. high density polyethylene C. hard durable polyethylene D. highly ductile polyethylene
B. high density polyethylene
A polymer is a large molecule A. made up of long chains of atoms held together by hydrogen bonds. B. made up of long chains of atoms covalently bonded together. C. made up of a large lattice structure held together by ionic bonds. D. always made up of identical monomer units.
B. made up of long chains of atoms covalently bonded together.
Proteins are polymers of amino acids held together by ______ bonds. A. protein B. peptide C. ester D. acid
B. peptide
The molecules that are added to polymers to make them softer and more pliable are known as A. monomers. B. plasticizers. C. pigments. D. rubber.
B. plasticizers
Electrolysis is a process that A. produces an electrical current. B. requires an electrical current. C. produces heat energy. D. requires heat energy.
B. requires an electrical current.
Whenever a substance is oxidized, A. it is called the oxidizing agent. B. some other substance must be reduced. C. it gains electrons. D. hydronium ions are produced.
B. some other substance must be reduced.
What is biodegradation? A. breaking up the plastics into small pieces before putting them into a landfill B. using bacteria and fungi to "eat" the waste plastic C. a way to dispose of natural polymers only D. breaking down polymers into carbon dioxide and water
B. using bacteria and fungi to "eat" the waste plastic
olyethylene can be represented by this drawing. A molecule of polyethylene has n=1000. What is the molar mass of this molecule? The atomic masses are: C = 12.01 g/mol; H = 1.01 g/mol. A. 1000 g/mol B. 14,030 g/mol C. 28,060 g/mol D. 56,120 g/mol
C. 28,060 g/mol
Why is it so expensive to ship hydrogen as a liquid as is often done with other gas? A. Hydrogen is very heavy to ship. B. Hydrogen is very dense to ship. C. Hydrogen has to be shipped at a very low temperature. D. Hydrogen in very flammable.
C. Hydrogen has to be shipped at a very low temperature.
When you try to stretch a piece of plastic bag, the length of the piece of plastic being pulled increases dramatically and the thickness decreases and this process is called A. Breaking C. Necking D. Mixing E. None of the above
C. Necking
How are HDPE and LDPE different? A. Only one is a member of the "Big Six." B. They are made from different monomers. C. One has branched chains while one is linear. D. One is made by addition polymerization, one by condensation.
C. One has branched chains while one is linear.
A monomer is A. a single polymer chain. B. a polymer made from only one component. C. a small molecule used to make a polymer chain. D. a polymer molecule that only contains a single element.
C. a small molecule used to make a polymer chain.
What moves in the salt bridge from the cathode to the anode? (see picture) A. electrons B. Zn+2 ions C. Cu+2 ions D. anions
D. anions
Which would be classified as a "synthetic" polymer? A. cellulose B. wool C. rubber D. nylon
D. nylon
During the chemical reaction in an electrochemical cell, A. a substance is oxidized and gains control over electrons. B. electrons travel from the cathode to the anode. C. oxidation may take place without there also being reduction. D. oxidation occurs at the anode.
D. oxidation occurs at the anode.
Polyvinyl chloride (PVC) is used in A. water bottles. B. CD cases. C. milk cartons. D. plumbing pipe
D. plumbing pipe