Chemistry Vocab

Question 1

Matter?

Answer 1

Anything that occupies space and has mass.

Question 2

Compound?

Answer 2

A substance composed of two or more elements in definite proportions.

Question 3

Mixture?

Answer 3

A substance composed of two or more different types of atoms or molecules combined in different proportions.

Question 4

Proportion?

Answer 4

A relationship between quantities such that if one varies, the other varies as well.

Question 5

Pure substance?

Answer 5

A substance made up of just one kind of element or compound.

Question 6

Property?

Answer 6

A characteristic used to distinguish one substance from another; remains the same no matter how much of the substance you have.

Question 7

Chemical property?

Answer 7

A property a substance displays only through changing its composition.

Question 8

Physical property?

Answer 8

A property a substance displays without changing its composition.

Question 9

Composition?

Answer 9

What a substance is made of.

Question 10

Physical change?

Answer 10

A change in which matter does not change its composition; is always a physical change.

Question 11

Chemical change?

Answer 11

A change in which matter does change its composition; a chemical reaction is always a this

Question 12

Phase change?

Answer 12

To change from one phase or state of matter to another.

Question 13

Dissolve?

Answer 13

A physical change in which one substance breaks apart another substance into microscopically small particles that are completely surrounded by the particles of the other substance; dissolving creates a solution.

Question 14

What is a solution?

Answer 14

A homogeneous mixture in which one substance, the solvent, breaks down the other substance, the solute, into smaller particles that are completely surrounded by particles of the solvent.

Question 15

Homogeneous?

Answer 15

Having the same composition throughout; the same in all its parts.

Question 16

Solvent?

Answer 16

A substance that dissolves another substance; is the substance doing the dissolving.

Question 17

Solute?

Answer 17

A substance that is dissolved in another substance; is the substance being dissolved.

Question 18

Element?

Answer 18

A substance that cannot be broken down into simpler substances.

Question 19

Atom?

Answer 19

The smallest identifiable unit of an element.

Question 20

Nucleus?

Answer 20

A small core containing most of the atom’s mass and all of its positive charge; made up of protons and neutrons.

Question 21

Proton?

Answer 21

A positively charged particle inside the nucleus of an atom.

Question 22

Neutron?

Answer 22

A nuclear particle that has no charge and nearly the same mass as the proton.

Question 23

electron

Answer 23

negatively charged particle that occupies most of the atom’s volume but contributes almost none of its mass.

Question 24

charge

Answer 24

a fundamental property of protons and electrons. Like charges repel; opposite charges attract.

Question 25

chemical symbol

Answer 25

one- or two–letter abbreviation for an element; are listed directly below the atomic number on the periodic table.

Question 26

atomic number

Answer 26

the number of protons in the nucleus of an atom.

Question 27

periodic table

Answer 27

arrangement of the elements in which atomic number increases from left to right and elements with similar properties appear in columns called families or groups.

Question 28

metal

Answer 28

those elements that tend toward the bottom-left side of the periodic table and tend to lose electrons in chemical reactions

Question 29

nonmetal

Answer 29

those elements that tend toward the upper-right side of the periodic table and tend to gain electrons in chemical reactions.

Question 30

metalloid

Answer 30

those elements that fall in the middle-right side of the periodic table that have properties between metals and nonmetals.

Question 31

semiconductor

Answer 31

compound or element that possesses intermediate electrical conductivity that can be changed and controlled

Question 32

isotope

Answer 32

an atom with the same number of protons but a different number of neutrons.

Question 33

atomic mass (atomic weight)

Answer 33

average mass of the atoms of an element

Question 34

ion

Answer 34

an atom with a charge

Question 35

molecule

Answer 35

two or more atoms grouped in well-defined clusters

Question 36

chemical formula

Answer 36

a group of chemical symbols and numbers that tells the number of atoms of each element in a compound

Question 37

valence electron

Answer 37

electron in an atom’s outermost shell

Question 38

ionic compound

Answer 38

compound formed between a metal and one or more nonmetals

Question 39

covalent compound

Answer 39

compound held together with covalent bonds; also called a molecular compound

Question 40

covalent bond

Answer 40

bond the results when two nonmetals combine in a chemical reaction. In this
the atoms share their electrons

Question 41

Electron level

Answer 41

Electron levels are regions around an atom’s nucleus where electrons exist.

Each level has a maximum number of electrons (e.g, Level 1 can only have 2 electrons in it). 2, 8, 18, 32
.
The outermost level contains valence electrons, which determine the chemical properties.