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Chemistry 1&2
test
Question | Answer |
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anything that has mass and takes up space | matter |
the study of the properties of matter and how matter changes | chemistry |
a single kind of matter that is pure, meaning it always has a specific makeup—or composition—and a specific set of properties | substance |
a characteristic of a pure substance that can be observed without changing it into another substance | physical property |
a characteristic of a pure substance that describes its ability to change into different substances | chemical property |
a pure substance that cannot be broken down into any other substances by chemical or physical means | element |
is the basic particle from which all elements are made | atom |
a force of attraction between two atoms | chemical bond |
groups of two or more atoms held together by chemical bonds | molecule |
a pure substance made of two or more elements chemically combined in a set ratio | compound |
shows the elements in the compound and the ratio of atoms | chemical formula |
made of two or more substances, elements, compounds, or both—that are together in the same place but are not chemically combined | mixture |
A mixture in which pure substances are unevenly distributed throughout the mixture. | heterogeneous mixture |
A mixture in which substances are evenly distributed throughout the mixture. | homogeneous mixture |
an example of a homogeneous mixture | solution |
a measure of the force of gravity on you | weight |
the measurement of the amount of matter in the object | mass |
The system of units (SI) used by scientists to measure the properties of matter. | International System of Units |
The amount of space that matter occupies | volume |
relates the mass of a material in a given volume | density |
any change that alters the form or appearance of matter but does not make any substance in the matter into a different substance | physical change |
A change in matter that produces one or more new substances | chemical change |
has a definite shape and a definite volume | solid |
Solids that are made up of crystals | crystalline solid |
the particles are not arranged in a regular pattern | amorphous solid |
has a definite volume but no shape of its own | liquid |
meaning “a substance that flows.” | fluid |
the result of an inward pull among the molecules of a liquid that brings the molecules on the surface closer together | surface tension |
a liquid’s resistance to flowing | viscosity |
A state of matter with no definite shape or volume. | gas |
The change in state from a solid to a liquid | melting |
The temperature at which a substance changes from a solid to a liquid; the same as the freezing point, or temperature at which a liquid changes to a solid. | melting point |
The change of state from liquid to solid | freezing |
The change from a liquid to a gas | vaporization |
The process that occurs when vaporization takes place only on the surface of a liquid. | evaporation |
occurs when a liquid changes to a gas below its surface as well as at the surface | boiling |
The temperature at which a liquid boils | boiling point |
The opposite of vaporization | condensation |
occurs when the surface particles of a solid gain enough energy that they form a gas | sublimation |
the very small center core of an atom | nucleus |
have a positive electric charge (indicated by a plus symbol, +) | proton |
have no charge | neutron |
move rapidly around the nucleus and have a negative electric charge | electron |
the number of protons in its nucleus | atomic number |
Atoms with the same number of protons and a different number of neutrons | isotope |
the sum of the protons and neutrons in the nucleus of an atom | mass number |
may be a diagram, a mental picture, a mathematical statement, or an object that helps explain ideas about the natural world | model |
the average mass of all the isotopes of that element | atomic mass |
A chart of the elements showing the repeating pattern of their properties. | periodic table |
A one- or two-letter representation of an element. | chemical symbol |