the knowledge obtained by observing natural events and conditions in order to discover facts and formulate laws or principles that can be verified or tested.
a series of steps followed to solve problems
the process of obtaining information using the senses.
a testable idea or explanation that leads to a scientific investigation.
any pieces of information acquired through observation or experimentation.
emergency medical care for someone who has been hurt or is sick.
a measure of the amount of matter in an object.
a measure of the size of an object or region in a three-dimensional space.
the ratio of the mass of a substance to the volume
a measure of how hot or cold something is.
a pattern, plan, representation, or description designed to show the structure of an object, system, or concept
a system of ideas that explains many related observations and is supported by a large body of evidence.
a descriptive statement or equation that reliably predicts events under certain conditions.
in an experiment, the factor that is deliberately manipulated.
the factor that changes as a result of manipulation.
one of two or more reference lines that mark the borders of a graph.
the number obtained by adding up the data and dividing the sum by the number of individuals.
the value of the middle term when data are arranged in order by size.
the most frequently occurring value in a set of data.
a measure of the slant of a line, rise over run
anything that has mass and takes up space.
a measure of the size of a body or region in three-dimensional space.
the curve at a liquid's surface by which one measure the volume of the liquid.
a measure of the gravitational force exerted on an object.
a characteristic of a substance that does not involve a chemical change such as density, color, or hardness.
the ratio of the mass of substance to the volume of the substance.
a change of matter from one form to another
a property of matter that describes a substance's ability to participate in chemical reactions.
a change that occurs when one or more substances change into entirely new substances.
states of matter
the physical forms of matter; solid, liquid, gas
state of matter in which the volume and shape of a substance are fixed.
state of matter that has a definite volume but not a defined shape.
a form of matter that does not have definite volume or shape.
a state of matter that starts as a gas and then becomes ionized, consists of free-moving ions and electrons and takes an electric charge.
change of state
the change of a substance from one state to another.
the change of state in which a solid becomes a liquid by adding heat.
the change of state from a liquid to a gas
the conversion of a liquid to a vapor
the change of state from a gas to a liquid.
the process in which a solid changes into a gas.
a substance that cannot be broken down or separated into simpler substances by chemical means
a sample of matter, either a single element or compound, that has definite chemical and physical properties.
an element that is shiny and that conducts heat and electricity well.
an element that conducts heat and electricity poorly.
an element that has properties of metals and nonmetals.
a substance made up of atoms of two or more different elements joined by chemical bonds.
a combination of two or more substances that are not chemically combined.
a homogeneous mixture throughout which two or more substances are uniformly dispersed.
in a solution, the substance that dissolves in a solvent
in a solution, the substance in which the solute dissolves.
the amount of particular substance in a given quantity of a mixture, solution, or ore.
the ability of one substance to dissolve in another at a given temperature.
the smallest unit of an element that maintains the properties of that element
a subatomic particle that has a negative charge
an atom's central region, which is made up of protons and neutrons.
a region around the nucleus of an atom where electron are likely to be found.'
a subatomic particle that has a positive charge and in located in the nucleus: the number of protons in the nucleus is the atomic number.
atomic mass unit
a unit of mass that describes the mass of an atom or molecule.
a subatomic particle that has no charge and is located in the nucleus of an atom.
the number of protons in the nucleus; same for all atoms of an element
an atom that has the dame number of protons as other atoms of the element but a different number of neutrons.
the sum of the numbers of protons and neutrons in the nucleus of an atom.
the mass of an atom expressed in atomic mass units.
an object's change in position relative to a reference point.
the total distance traveled divided by the total time taken.
the speed of an object in a particular direction
the rate at which velocity changes over time; must change in speed, direction, or both.
a push or pull exerted on an object in order to change the motion of the object
the SI unit for force
the combination of all the forces acting on an object.
a force that opposed motion between two surfaces that are in contact.
a force of attraction between objects due to their masses.
the constant velocity of a falling object when the force of air resistance is equal in magnitude and opposite in direction to gravity.
the motion of a body when only gravity is acting on it.
the curved path that an object follows when thrown, or projected toward the surface of Earth.
the tendency of an object to resist being moved or resist a change in speed or direction.
a non solid state of matter in which the atoms or molecules are free to move past each other
the amount of force exerted per unit area of a surface.
the SI unit of pressure.
the pressure cause by the weight of the atmosphere
the upward force that keeps an object immersed in or floating on a liquid
the buoyant force on an object in a fluid is an upward force equal to the weight of the volume of fluid that the object displaces.