Science Midterm

physical change

Evaporation is what kind of change?

thermonuclear fusion

Fusion brought about by high temperatures is called __________?

mass number

How are isotopes identified?

smaller

How is the mass of a beta particle in comparison to an alpha particle?

Astherosphere

In which interior layer does convection occur?

same number of protons and neutrons

Isotopes of an element have....

gaseous

Particles in the _______ phase(s) are moving so rapidly that they separate from one another altogether.

1800

Protons are about ___ times massive as electrons

emit radiation

Radioactivity is a tendency for an element or a material to...

related to one another, but are not the same thing

Science and technology are...

humankind's beginnings

Science is a body of knowledge that goes back to...

all three have different domains.

Science, art and religion do not contradict one another because:

same

The atomic number of an element is the _________as its protons and neutrons

critical mass

The minimum mass of fissionable material in a reactor or nuclear bomb that will sustain a chain reaction is?

Before humans appeared on earth

The origins of radioactivity go back to...

none of the above

The phase in which atoms and molecules no longer move is the...

one

There are _________ electrons in a single covalent bond.

Molecules are so sticky

Water has such a relatively high boiling point because water?

a pattern of distinct frequencies of light

What does an atomic spectrum tell us about an element?

Imbalance of neutrons and protons

What does unstable atomic nuclei mean?

Products that start a new reaction are released.

What happens in a chain reaction?

the force of attraction between two atoms that holds them together within a compound

What is a chemical bond?

a separation of charge that occurs in a chemical bond because of differences in the electronegativites of the bonded atoms.

What is a dipole?

It is the time it takes for 1/2 of the material to undergo radiodecay.

What is a half-life?

A rem is a unit for measuring radiation exposure.

What is a rem?

any molecole that is made mostly of carbon with no metals in it

What is an organic compound?

an electron ejected from a nucleus

What is beta particle?

Period

What is each horizontal row called in a periodic table?

A mixture can be physically separated into its components; a compound cannot be physically separated into its components.

What is the difference between a compound and a mixture?

Nuclear Fuel, Control Rods, Moderator, and liquid

A Fission reactor contains which four components?

Physical; Chemical

A ____ change imposes a new set of conditions on the same material while a _____ change forms a new material that has its own unique set of properties.

mixture;physical

A _____ is a collection of two or more pure substances. It can be separated by a _____ means.

compound

A combination of two or more substances in which they no longer retain their chemical properties is called a(n)

different

A compound is a substance that consists of atoms of ____ elements

The atoms (mass) of gasoline are converted into exhaust fumes.

A friend argues that if amss were really conserved he would never need to refill his gas tank. What explanation do you offer your friend?

to help evaporation occur in its mouth and bronchial tract.

A hot dog pants....

particles

All solids, liquids and gases are made up of?

positive

Alpha a type of radiation carries which charge?

ground state

An atom reaches the lowest energy level called the _______.

ion

An atom that has a net electric charge is called a/an ________

Conducting heat

Metals are BEST indicated by...

are strong but can be bent.

Metals are useful for the structural support of buildings because they

The electrons on the atoms repel other electrons on other atoms when they get close.

Since atoms are mostly empty space, why don't objects pass through one another?

Because there is a lot of space between gas particles

Why are gases so much easier to compress into smaller volumes?

The sea of electrons helps pass charges through the metal.

Why are metals able to conduct electricity?

Metals can be efficiently extracted from them.

Why are ores so valuable?

Atoms are smaller than wavelengths of visible light

Why can't atoms be seen with visible light?

The periodic table lists only elements made of one kind of material. Dirt is a mixture of elements and compounds.

Why isn't dirt listed in the periodic table?

Your first friend is correct. Radioactive isotopes emit alpha particles which, in turn, capture electrons and become helium atoms.

Your friend says that the helium used to inflate balloons is a product of radioactive decay. Another friend says "no way." With whom do you agree?

radiation

_____ is the process in which unstable atomic nuclei transform and emit radiation.

diffusion

_______ is the tendency of molecules to move from an area of high concentration to one of low concentration.

chemical

_______ properties are properties that characterize the ability of a substance to react with other substances or to transform from one substance into another.

Atoms

__________ make up all matter around us.

blue

___________ light has the most energy per photon.

The air we exhale has more mass; breathing causes you to lose weight.

When we breathe we inhale oxygen, No Image, and exhale carbon dioxide, No Image, plus water vapor, No Image. Which likely has more mass, the air that we inhale or the same volume of air we exhale?

in the explosions of ancient stars

Where did the atoms that make up a newborn baby originate?

Inside the nucleus of a neutron

Where does a beta particle originate?

Oxygen

Which of the following is necessary for burning (combustion)?

light

Which of the following would not be considered matter?

covalent bond

An electrical attraction in which atoms are held together by their mutual attraction for shared electrons is called ________.

atom

An element is a material made of one kind of ______

proton

An ion is an ____ that has lost or gained one or more electrons.

The heat from a nuclear reaction is used to boil water.

How do fission power plants work?

12 hours

If a material has a half-life of 24 hours, how long do you have to wait until the amount of radioisotope is 1/4 its original amount?

75.5%

If an alcoholic beverage has a proof of 151, what is the percentage of alcohol in the beverage?

the results are not considered valid

If experimental findings are not reproducible...

Kinetic

In Nuclear Fission the energy is released in the form of _____ energy.

Energy is released, so the products have less mass-the initial uranium has more mass

In a nuclear fission reaction, which has more mass, the initial uranium or its products?

The amount of energy released in the fusion of large nuclei is very large.

In fission....

a synthesis of a large body of well-tested knowledge

In science, a theory is...

.01

One rad is equal to ____ J of radiant energy absorbed per kilogram of tissue.

distance from

The potential energy of an electron depends on its _____ the nucleus

speculation

The statement, "There are regions beneath Earth's crust that will always be beyond the reach of scientific investigation," is a...

Alpha, Beta, Gamma

The three types of radiation are ___ , ____ , and _____.

Atomic mass

The total mass of an atom is called_______

Subtracting its atomic number from its mass number

The total number of neutrons in an isotope can be calculated by ____________

Carbon tetrabromide

What is the name of the Compound with the formula CBr4?

Atom

What is the smallest unit of an element?

It is the outermost shell of electrons in an atom

What is the valence shell?

chemical change

What kind of change occurs when copper reacts with carbon dioxide and water?

gets no second chance in the scientific community.

When a scientist is dishonest and reports false information, he or she...

Ion

When an atom gains or loses an electron, it is classified as a ___________.

Alpha particles are more harmful than Gamma rays.

Which of the following is not true about an Alpha Particle.

determining the lightest and strongest metal to be used for an airplane wing.

Which of the following would be considered applied research?

C) Gamma

Which of the three rays is most like an X-ray?

gamma

Which radiation carries no charge?

a material that is made up of a combination of atoms bonded together

Which statement best describes a compound?

Isaac Newton

Who discovered Gravity?

max planck

Who identified each discrete parcel of light energy as a quantum?