Eighth Grade Final Exam Review

What is 78,900,000,000 expressed in scientific notation

atoms often join so that each atom will have

the most reactive group of nonmetals on the periodic table consist of the _________

digesting food is an example of

silicon, a semiconductor, is often found in

which is not a family of the periodic table

A loaf of bread weighs 1,362 g. The weight in kilograms is

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

a compound consisting of lithium and oxygen would be named ___________

spoonful of salt into 1 liter of water and stir. the resulting liquid is an example of a(n)

an atom of which of the following elements is unlikely to form a negatively charged ion

the order of elements in the modern periodic table is based on an element's

Mendeleev studied the properties of the elements and looked for

Pascal's principle states that a fluid in equilibrium enclosed by a vessel exerts pressure

the number of energy levels that are filled in atoms is determined bu the number of

which of the following statements about the modern model of the atom is true

astronomers use __________ to view distant objects

alkali metals form compounds by

What are the main branches of natural science

unlike a mixture, a pure substance has

group 18 noble gases are relatively inert because

unlike gas, a plasma

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

if the volume of a contained sample of a gas is decreased, its pressure is

formaldehyde, CH2O, and acetic acid, C2H4O2, have the same empiricle formula but different

the most reactive group of metals on the periodic table consist of the _________ metals

elements in a family often have a similar

a tool used by physicists to smash atoms is a

which of the following is an element

Maria is 123 centimeters tall. Her height in meters is

which of the following is an example of a chemical property

a group's elements react similarly because of their _____________

when an object floats, the buoyant force is greater than the _______ of the object

the process of a liquid becoming a solid is called

using scientific knowledge for practical applications is called ________

a mathematical representation of an object or event is a(n) ___________

a gas becomes a liquid through a process called

the only state of matter with definite shape and form is ____________

A scientific model is a

each molecule of table sugar, O12H22O11, contains

in ionic compounds, the positively charged ions are formed from _____________ elements

the metals are divided into families based on the number of _______ they have

elements called ________ can conduct heat and electricity only under certain conditions

each molecule of hydrochloric acid, HCL. contains one atom of hydrogen and

matter is defined as anything that

The decimal equivalent of 10^-2 is

What do scientists who do pure science do

the smallest unit of a substance that behaves like the substance is a(n)

Avogadro's number is defined as the number of particles in

copper is good conductor of electricity because its electrons

What are the two main branches of science

a compound is held together by

which element is a semiconductor

how does the density of an object that sinks into a fluid compare to the density of the fluid

a protein is a polymer that is made of

molar mass is defined as

knowing the chemical properties of a substance will tell you how the substance

elements in the same group of the periodic table have same properties because they have = # of

the name dinitrogen tetraoxide tells you that this compound contains

Thomson's study of cathode rays revealed that atoms contained - charged particles called ______

the _____ is the SI unit that is used for counting small particles, such as atoms

in which substance do the molecules have the strongest attractions to one another

the chemical formula for dinitrogen pentaoxide is __________

For a scientific theory to be valid, it must allow you to

when two chlorine atoms bond, they _________ a pair of electrons

alkali metals are extremely reactive because they

unlike other states of matter, ________ expand to fill their containers

the name for the compound with the formula CuBr2 would be written as

a possible answer to a scientific problem is a(n) _______

an important science skill is critical thinking. This means

Which prefix means one one-hundredth

during which of the following changes of state do atoms or molecules become less ordered

gases take up a lot of space because gas molecules

two or more elements that chemically combine are referred to as a ___________

the simplest organic compound is

isotopes of an element have different __________

a chemical formula is C12H22O11. How many oxygen atoms are in each sugar molecule

steel has density of 7.8 g/cm^3. Find the mass of a block of steel with a volume of 600.0 cm^3

which statement is true according to Dalton's theory

most halogens form compounds by

Which SI prefix means one-thousandth (1/1000)

an unified atomic mass unit is equal to

the chemical formula for magnesium bromide is ______________

which of the following is made of at least two different types of atoms

a state of matter that is NOT a fluid is

a(n) _______ measurement is one that is as exact as possible

the proper name for P4S3 is __________

elements that are usually shiny are ______________

polymers are large organic molecules that are made of

in the SI system, the prefix _________ means one thousand

the simplest formula for a covalent compound is its __________

an atom's mass number equals the number of

the speed of light is about 3*10^8 m/s. how would this be written in conventional notation

covalent bonds are formed between

the _________ of a substance is defined as its mass divided by its volume

aluminum, oxygen, and carbon are each _________

if a fixed sample of gas increases in temperature, at a contrast pressure, its volume _________

which of the following is NOT an example of a physical property

the elements called ________ are not metals but have some properties of metals

the process of a liquid becoming a gas is called

the most common state of matter in the universe is ________

how many chemical bonds can carbon form with other atoms

the number 4.045 has _____ significant figures

A substance that cannot be broken down into simpler substances is a(n)

when copper combines with oxygen to form copper (II) oxide, the charge of the copper ion is

the nucleus of an atom has a ________ electric charge

nonmetals are sometimes called _____ because they do not conduct heat or electricity well

a measure of the average kinetic energy of the particles in an object is called

each molecule of iron oxide (Fe2O3) contains ______ iron atom(s)

the components of __________ can be separated because they are not chemically combined

the kinetic theory helps to explain the differences between

length, mass, time, and temperature are four of the seven SI _________ units

metals tend to be

the compound _______ is an example of an ionic compound

elements that share properties of both metals and nonmetals are called

some elements are ________ because their outermost energy levels are only partially filled

average atomic mass of potassium is approximately 39 u. what's the mass of 2.0 mol of potassium

according to Rutherford's model of the atom, electrons behave like

the law of conservation of ________ states that mass cannot be created or destroyed

one of the important ideas about Mendeleev's periodic table was that he predicted new _________

which of the following is NOT an example of a physical property

a mole is an SI base unit that describes the

the name for the compound with the formula CaCl2 would be written as

the forces that hold different atoms or ions together are

A measurement that is accurate is one that

Rutherford's gold-foil experiment showed that an atom's + charge is mainly in the atom's _____

A scientific theory is an explanation that

which statement about an element's average atomic mass is correct

Bohr's model of the atom compares electrons with ______________

which statement about noble gases is correct

which of the following is an example of a physical change

wheat ground into flour is an example of a _______ change

The SI unit for measuring temperature is the

a lithium ion is much less reactive than a lithium atom because it

as one moves from left to right across a period in the modern periodic table, elements become

a substance has a mass of 360 g and a volume of 7.5 mL. what is its density

a(n) ________ bond is formed when atoms share pairs of electrons

Mendeleev stated a new ___ in his periodic table when properties repeated

fluid pressure decreases when the fluid speed increases according to _________ principle

which of the following is an example of a chemical change

unlike a plasma, a gas

gold is usually found in a pure form in nature because it is NOT _______

what is the mass in grams of 0.75 mol of sulfur, which has a molar mass of 32.07 g/mol

the chemical symbol for sulfuric acid is H2SO4. how many hydrogen atoms are in sulfuric acid

the force keeping an object floating on a liquid is called

the chemical formula for potassium oxide is _____

a change in color during a reaction is often a sign that a ___________ change has occured

a(n) ______ is the smallest unit of a substance that retains the properties of that substance

Scientists test a hypothesis by

which statement about the atom's nucleus is correct

in a metallic bond, the nucleus of one atom is attracted by a nearby

fluid pressure is always directed

if the average atomic mass of carbon is 12.01 u, each mole of pure carbon will have a mass of

ionization refers to the process of

which statement about the alkali metals is correct

an example of a chemical property is a substace's

which state of matter has a definite volume, but not a definite shape

which statement about the modern model of the atom is NOT true

which of the following is an example of a mixture

the distance between the nuclei of to bonded atoms is the ___________

any factor in an experiment that can change is referred to as a(n) __________

valence electron of a lithium atom is easily removed to form a lithium ____ with a charge of 1+

an atom gains energy by absorbing a light particle called a(n) ___________

according to Bohr's theory, and electron's path around the nucleus defines its

Thomson's cathode-ray tube experiment supported the theory that __________ exist inside an atom

A scientific law is

grinding quartz crystals down to produce sand causes a ______________

Mendeleev version of the periodic table, based his arrangement of the element on an element's

oxygen's atomic number is 8. this means that an oxygen atom has

the science of what matter is made of and how it changes is called

ice floats because the density of ice is ______ the density of water

average atomic mass of the element cesium is 132.91 u. what is the mass of 3.00 mol of cesium

a solid becomes a gas through a process called