Chemistry Test

Question 1

Substances can be classified into what two categories?

Answer 1

Elements and compounds

Question 2

What is a substance that can’t be broken down into simpler substances

Answer 2

An element

Question 3

What is the smallest particle of an element

Answer 3

An atom

Question 4

Why does an atom have a fixed composition

Answer 4

Because it contain only one type of element

Question 5

What is a substance that is made from two or more simpler substances and can be broken down into those simpler substances

Answer 5

A compound

Question 6

What does a compound always contains

Answer 6

Two or more elements joined at fixed proportion

Question 7

What is any ability to produce a change in the composition of matter

Answer 7

A chemical property

Question 8

What can only be observed when the substances in a sample of matter are changing in different substances

Answer 8

Chemical properties

Question 9

What is a materials ability to burn in the presence of oxygen

Answer 9

Flammability

Question 10

What is the property that describes how readily a substance combines chemically with another substance

Answer 10

Reactivity

Question 11

What occurs when a substance reacts and forms one or more new substances

Answer 11

A chemical change

Question 12

What are the three common types of evidence for a chemical change

Answer 12

Change in color, production of gas, and the formation of a precipitate,

Question 13

What is any solid that forms a liquid mixture called

Answer 13

A precipitate

Question 14

What is the difference between a chemical change and a physical change

Answer 14

Chemical change: changes composition of matter

Physical change: composition of matter stays the same

Question 15

What is a dense positively charged center of the Atom

Answer 15

The nucleus

Question 16

What are the subatomic particles

Answer 16

Protons, electrons, neutrons

Question 17

What is a positively charged subatomic particle found in the nucleus of an Atom

Answer 17

Proton

Question 18

What is a negatively charged subatomic particle found outside nucleus of an atom

Answer 18

Electron

Question 19

What is a neutral subatomic particle that is found in the nucleus

Answer 19

Neutron

Question 20

Matter that always has exactly the same composition is classified as a what?

Answer 20

A pure substance

Question 21

Protons electrons and neutrons can be distinguished by what

Answer 21

Mass, charge, and location in Atom

Question 22

What of elements equals the number of protons in an atom of that element

Answer 22

Atomic number

Question 23

Atoms of different elements have different numbers of what

Answer 23

Protons

Question 24

What is the sum of protons and neutrons in the nucleus in an Atom

Answer 24

The mass number

Question 25

The possible energies that electrons in an Atom can have Are called what

Answer 25

Energy levels

Question 26

What's in a Atom can move from one energy level to another when the atom gains or loses energy

Answer 26

An electron

Question 27

What is a visual model of the most likely locations for electrons and Atom

Answer 27

Electron cloud

Question 28

Scientists use what to describe the possible locations of electrons around the nucleus

Answer 28

An electron cloud model

Question 29

What is a region of space around the nucleus were an electron is most likely to be found

Answer 29

An orbital

Question 30

What is a good approximation of how electrons behave in the orbitals

Answer 30

An electron cloud

Question 31

What is the arrangement of electrons in the orbitals of an Atom

Answer 31

An electron configuration

Question 32

What is the most stable electron configuration

Answer 32

When electrons are in their orbitals with the lowest possible energies

Question 33

What is it called when all the electrons in and atom have the lowest possible energies

Answer 33

Ground state

Question 34

What is an arrangement of elements in column based on a set of properties that repeat from Row to row

Answer 34

A periodic table

Question 35

What are the elements arranged by in the modern periodic table

Answer 35

Atomic number

Question 36

What is a value that depends on the distribution of elements isotopes in nature and the masses of those isotopes

Answer 36

Atomic mass

Question 37

What is defined as one twelfth the mass of a Carbon – 12 Atom

Answer 37

Atomic mass unit

Question 38

What are elements classified as

Answer 38

Metals, nonmetals, metalloids

Question 39

What are elements that are good conductors of electric current and heat

Answer 39

Metals

Question 40

What are elements that form a bridge between the elements on the left and right sides of the table

Answer 40

Transition metals

Question 41

What are elements that are poor conductors of heat and electric current

Answer 41

Nonmetals

Question 42

What are elements with properties that fall between those of metals and nonmetals

Answer 42

Metalloids

Question 43

Across a period from left to right do elements become more nonmetallic or more metallic in their properties

Answer 43

More nonmetallic

Question 44

What is an electron that is in the highest occupied energy level of an Atom

Answer 44

A valence electron

Question 45

Why do elements in a group have similar properties

Answer 45

Because they have the same number of valence electrons

Question 46

What are elements in group 1A called

Answer 46

Alkali metals

Question 47

The reactivity of alkali metals increases from the top of group 1A bottom or bottom to top

Answer 47

Top to bottom

Question 48

What are elements in group 2A called

Answer 48

Alkaline earth metals

Question 49

How are differences in the reactivity among alkaline earth metals shown

Answer 49

By the way they react to water

Question 50

The elements in group 8A are called what

Answer 50

Noble gases

Question 51

What are colorless and odorless and extremely unreactive

Answer 51

The noble gases