Science Chapter 3 Vocab Flashcards
Electrons
A tiny, negatively charged particle that moves around the outside of the nucleus of an atom.
Atom
Smallest particle that can still be considered and element
Nucleus
The central core of an atom which contains protons and neutrons
Protons
Small, positively charged particles that are found in the nucleus of an atom.
Energy level
A region of an atom in which electrons of the same energy are likely to be found.
Neutron
A small particle in the nucleus of the atom, with no electrical charge.
Atomic number
The number of protons in the nucleus of an atom.
Isotopes
An atom with the same number of protons and a different number of neutrons from other atoms of the same element.
Mass number
The sum of protons and neutrons in the nucleus of an atom.
Atomic mass
The average mass of all the isotopes of an element.
Periodic Table
An arrangement of the elements showing the repeating pattern of their properties.
Chemical Symbol
A one- or two-letter representation of an element.
Periods
- A horizontal row of elements in the periodic table
Metals
A class of elements characterized by physical properties that include shininess, malleability, ductility, and conductivity.
Group
Elements in the same vertical column of the periodic table; also called family.
Luster
The way a mineral reflects light from its surface.
Malleable
A term used to describe material that can be hammered or rolled into flat sheets.
Ductile
A term used to describe a material that can be pulled out into a long wire.
Thermal Conductivity
The ability of an object to transfer heat.
Electrical Conductivity
The ability of an object to carry electric current.
Reactivity
The ease and speed with which an element combines, or reacts, with other elements and compounds.
Corrosion
The gradual wearing away of a metal element due to a chemical reaction.
Alkali Metals
An element in Group 1 of the periodic table.
Alkaline Earth Metals
An element in Group 2 of the periodic table.
Transition Metals
One of the elements in Groups 3 through 12 of the periodic table.
Nonmetal
An element that lacks most of the properties of a metal.
Diatomic Molecule
A molecule consisting of two atoms.
Halogens
An element found in Group 17 of the periodic table.
Noble gases
An element in Group 18 of the periodic table.
Metalloid
An element that has some characteristics of both metals and nonmetals.
Semiconductors
A substance that can conduct electric current under some conditions.
Radioactive decay
The process in which the nuclei of radioactive elements break down, releasing fast-moving particles and energy.
Nuclear reaction
A reaction involving the particles in the nucleus of an atom that can change one element into another element.
Radioactivity
The spontaneous emission of radiation by an unstable atomic nucleus.
Alpha particle
A particle given off during radioactive decay that consists of two protons and two neutrons.
Beta particle
A fast-moving electron that is given off as nuclear radiation.
Gamma rays
Electromagnetic waves with the shortest wavelengths and highest frequencies.
Half-life
The time it takes for half of the atoms of a radioactive element to decay.
Tracer
A radioactive isotope that can be followed through the steps of a chemical reaction or industrial process.
