Chapter One

• accuracy is how closely a measurement aligns with a correct value
• an atom is the smallest particle of an element that can enter into a chemical combination
• Celsius (°C) is a unit of temperature; water freezes at 0 °C and boils at 100 °C on this scale
• chemical change is a change producing a different kind of matter from the original kind of matter
• chemical property is behavior that is related to the change of one kind of matter into another kind of matter
• chemistry is the study of the composition, properties, and interactions of matter
• a compound is a pure substance that can be decomposed into two or more elements
• cubic centimeter (cm3 or cc) is the volume of a cube with an edge length of exactly 1 cm
• cubic meter (m3)is the SI unit of volume
• density is the ratio of mass to volume for a substance or object
• dimensional analysis is a (also, factor-label method) versatile mathematical approach that can be applied to computations ranging from simple unit conversions to more complex, multi-step calculations involving several different quantities
• an element is a substance that is composed of a single type of atom; a substance that cannot be decomposed by a chemical change
• an exact number is a number derived by counting or by definition
• an extensive property is a property of a substance that depends on the amount of the substance
• Fahrenheit is a unit of temperature; water freezes at 32 °F and boils at 212 °F on this scale
• gas is a state in which matter has neither definite volume nor shape
• a heterogeneous mixture is a combination of substances with a composition that varies from point to point
• a homogeneous mixture is a (also, solution) combination of substances with a composition that is uniform throughout
• a hypothesis is a tentative explanation of observations that acts as a guide for gathering and checking information
• an intensive property is a property of a substance that is independent of the amount of the substance
• kelvin (K) is an SI unit of temperature; 273.15 K = 0 ºC
• a kilogram (kg) is a standard SI unit of mass
• a law is a statement that summarizes a vast number of experimental observations, and describes or predicts some aspect of the natural world
• the law of conservation of matter is when matter converts from one type to another or changes form, there is no detectable change in the total amount of matter present
• length is a measure of one dimension of an object
• liquid is a state of matter that has a definite volume but indefinite shape
• a liter (L) is a (also, cubic decimeter) unit of volume; 1 L = 1,000 cm3
• macroscopic domain is a realm of everyday things that are large enough to sense directly by human sight and touch
• mass is a fundamental property indicating amount of matter
• matter is anything that occupies space and has mass
• a meter (m) is a standard metric and SI unit of length; 1 m = approximately 1.094 yards
• a microscopic domain is a realm of things that are much too small to be sensed directly
• a milliliter (mL) is 1/1,000 of a liter; equal to 1 cm3
• a mixture is matter that can be separated into its components by physical means
• a molecule is a bonded collection of two or more atoms of the same or different elements
• a physical change is a change in the state or properties of matter that does not involve a change in its chemical composition
• a physical property is a characteristic of matter that is not associated with any change in its chemical composition
• plasma is a gaseous state of matter containing a large number of electrically charged atoms and/or molecules
• precision is how closely a measurement matches the same measurement when repeated
• a pure substance is a homogeneous substance that has a constant composition