Science – Chapter 8
Unlock all answers in this set
Unlock answersquestion
A large, complex molecule built from smaller molecules joined together is a(n): composite polymer monomer alloy
answer
polymer
question
If a polymer is compared to a long train of identical train cars, each car represents a: monomer composite alloy chemical bond
answer
monomer
question
A natural polymer that gives shape to plant cells is: silk nylon cellulose wood
answer
cellulose
question
Which of the following is an example of a synthetic polymer? cellulose a spider's web a protein plastic
answer
plastic
question
A polymer may be combined with one or more substances to make a new material called a(n): alloy monomer ceramic composite
answer
composite
question
Which material is an example of a natural composite? fiberglass wood Kevlar nylon
answer
wood
question
A substance made of two or more elements that has been the properties of metal is a(n): polymer monomer alloy ceramic
answer
alloy
question
Which of the following is an alloy? bronze tin copper gold
answer
bronze
question
What is an advantage that alloys might have over many pure metals? Alloys occur naturally Alloys resist rust Alloys are weaker Alloys can bend easily
answer
Alloys resist rust
question
What is the advantage in making an alloy by mixing the elements as powders and then heating them? The amount of each metal does not have to be carefully measured; The metals blend at lower temperatures so they may be quickly molded; Less pressure is needed; More energy is used.
answer
The metals blend at lower temperatures so they may be quickly molded;
question
Steel is an alloy of one or more elements combined with: copper gold iron lead
answer
iron
question
Which of the following properties is NOT characteristic of steel? hardness resistance to corrosion strength reacts readily with air
answer
reacts readily with air
question
An alloy called amalgam, which is used by dentists to fill cavities, is made with: mercury and silver lead and gold nickel and chromium iron and carbon
answer
mercury and silver
question
Hard, crystalline solids made by heating clay and other mineral materials to high temperatures are: alloys glasses ceramics polymers
answer
ceramics
question
One useful property of ceramics is their ability to: resist moisture conduct electricity melt at low temperatures resist breaking when struck
answer
resist moisture
question
The outside of the space shuttle is protected from extremely high heat during reentry by an outer covering of: alloys ceramic tiles glass pure metals
answer
ceramic tiles
question
The main ingredient used to make glass is: water lead sand crystal
answer
sand
question
What materials are being used to replace copper telephone and cable television lines? composites optical fibers alloys polymer fibers
answer
optical fibers
question
Which of the following is NOT a useful property of glass? bends light resists heat carries light messages conducts electricity
answer
conducts electricity
question
Reactions involving the particles in the nucleus of an atom are called: physical reactions chemical reactions nuclear reactions composite reactions
answer
nuclear reactions
question
During radioactive decay, atomic nuclei of unstable isotopes: give off nuclear radiation are broken down by radioactive bacteria form chemical bonds are unchanged
answer
give off nuclear radiation
question
A piece of paper or a thin piece of metal will provide protection from: alpha radiation beta radiation gamma radiation all forms of nuclear radiation
answer
alpha radiation
question
Beta radiation consists of particles that are identical to: helium nuclei hydrogen atoms X-rays electrons
answer
electrons
question
Measurements of half-life make radioactive isotopes useful for: radiation therapy tracing oil spills building shields to absorb nuclear radiation determining the ages of rocks and fossils
answer
determining the ages of rocks and fossils
question
The half-life of an isotope is the length of time needed for half the atoms in the sample to: decay double in size become radioactive rust
answer
decay
question
Radioactive isotopes called _________ can be used to detect medical problems and to treat some diseases: beta particles tracers gamma radiation alpha particles
answer
tracers
question
Radiation therapy is effective because it: allows ancient fossils to be dated destroys human cells makes use of radioactive isotopes as fuel identifies weak spots in water pipes
answer
destroys human cells
question
The disposal of radioactive materials must be carefully managed because they are expensive take up too much space in landfills sometimes have long half-lives may be traced
answer
sometimes have long half-lives
question
YOu find the mass number of an isotope by: adding the number of protons and electrons; subtracting the number of protons from the number of neutrons; adding the number of protons, electrons, and neutrons; adding the number of protons and neutrons.
answer
adding the number of protons and neutrons
question
T/F - A polymer is a complex molecule made from smaller units called MONOMERS.
answer
T
question
T/F - Two or more substances may be combined to produce a new material that works better than either one alone. This new material is called a PLASTIC
answer
F - Alloy
question
T/F - In every alloy, a least one of the components is METAL
answer
T
question
T/F - BRASS is an alloy of iron with other elements.
answer
F - Bronze
question
T/F - GOLD ALLOYS resist moisture, do not conduct electricity, and can withstand very high temperatures
answer
F - Steel
question
T/F - CLAY is a clear, solid material with no crystal structure
answer
F - Glass
question
T/F - Unstable isotopes decompose and release fast-moving particles and energy in a process called RADIOACTIVE DECAY
answer
T
question
T/F - The time needed for half the atoms in a radioactive isotope to decay is known as the RADIATION PERIOD of the isotope.
answer
F - Half-life
question
T/F - The ATOMIC NUMBER is the sum of the numbers of protons and neutrons in the nucleus of an atom.
answer
F - Mass number
