Physical Science Midterm Exam Review

the smallest unit of an element that maintains the properties of that element

atom

a substance that cannot be broken down into a simpler substance by chemistry

element

A sample of matter that has definite chemical and physical properties

pure substance

a mixture that is mixed uniformly

homogenous

a mixture that is not mixed evenly

heterogenous

a substance made of atoms of two or more elements

compound

physical science is divided up into physics and

chemistry

the kilogram is a unit that measures

mass

what refers to the change from a liquid to a gas?

evaporation

the volume of a gas decreases when pressure increases because the gas particles get

pushed together

as the pressure of a gas at a constant temperature decreases, the volume

increases

when particles condense, they start to

slow down and clump together

Pascal's principle states that a contained fluid exerts pressure

equally in all directions

compared to less massive particles at the same temperature, more massive particles

move more slowly

the process of a liquid becoming a gas is called

evaporation

Archimedes principle states that the buoyant on a(n) _

is equal to the weight of the displaced volume of fluid

object in the fluid

liquids and gases are both

fluids

buoyant force is an _ force exerted on an object immersed or floating on a liquid

upward

the kinetic theory states that the higher the temperature, the faster

the particles that make up a substance move

as the speed of a moving liquid increases, its pressure

decreases

how does the density of an object floating in a fluid compare to the density of the fluid?

the floating object is less dense

valence electrons determine an atom's

chemical properties

do neutrons have a charge?

no, they are neutral

how do you figure out the number of neutrons that an atom has?

take the atomic mass - the atomic number

an element's atomic number is equal to its number of

protons

how do they figure out the average atomic mass of an element?

it is a weighted average, so common isotopes have a greater effect than uncommon isotopes

atoms of elements that are in the same group have the same number of

valence electrons

which group on the periodic table includes the alkali metals?

group 1

*Remember hydrogen is in this group but not a metal

carbon and other nonmetals are found on which side of the periodic table?

the right side

each column on the periodic table is

a group

atoms that gain or lose electrons are called

ions

elements that have this number of valence electrons tend to be highly reactive, form +1 ions, and become charged

one

elements in this group form ions with a -1 charge

group 17 - the halogens

the three main groups of elements are metals, nonmetals, and

semiconductors

most elements are

metals

most nonmetals are

brittle

elements in an element family have similar

chemical properties

noble gases are/are not highly reactive

are not. they have a full outer orbital and don't want to form bonds

the process of losing or gaining electrons is called

ionization

group 18 noble gases are relatively inert because

they have 8 valence electrons

metals tend to be

good conductors of heat

are anions a group on the periodic table?

no

often atoms join so that each atom will have

an outermost energy level that is full of electrons

an ionic bond is a bond that forms between

ions with opposite charges

in what type of bond do atoms share electrons?

covalent

a carbon atoms can form bonds with four other atoms because

it has 4 valence electrons

which type of bond is weaker: the attraction between ions or the attraction between molecules?

the attraction between molecules

atoms sometimes form bonds to become

more stable

copper atoms are held together by _ bonds.

metallic

atoms that are called ions have a charge because they have lost or gained what?

electrons

covalent bonds are formed between

nonmetal atoms

what type of bond forms positive and negative ions?

ionic

what type of bond makes compounds with relatively low melting points?

covalent

what type of bond usually occurs between nonmetals?

covalent

what type of bond is caused by transferring electrons?

ionic

what type of bond allows copper to bend and conduct electricity?

metallic

in a solution, what do we call the substance that the solute dissolves in?

the solvent

which one would cause a solution to dissolve better: cooling it down, add more of the solvent, stirring it, or adding more of the solute?

stir it

what produces hydronium (H+) ions in water?

acid

what is produced when you add a base to water?

hydroxide (OH-) ions

which one tastes bitter and soapy: acid, base, or salt?

base

what is the actual cause of radioactivity?

neutrons decay

what type of radioactive decay gives up two protons and two neutrons?

alpha

which type of radioactive decay happens when a high energy particle of light is emitted?

gamma

which type of radioactive decay happens when a neutron turns into a proton?

beta

what actually keeps the nucleus together, even though the protons repel each other?

strong nuclear force

which one splits nuclei into smaller nuclei and releases neutrons: nuclear fission or nuclear fusion?

nuclear fission

which one fuses nuclei together to form a heavier nucleus: nuclear fission or nuclear fusion?

nuclear fusion

which one is how the sun gets its energy: nuclear fission or nuclear fusion?

nuclear fusion

which one is used in nuclear reactors: nuclear fission or nuclear fusion?

nuclear fission