Chapter 2 & 3 Vocab Flashcards
Matter
Anything that has mass and takes up space.
Solid
A sample of matter that contains its shape and density when not confined.
Liquid
A substance that flows freely but is of constant volume.
Gas
A substance or matter in a state in which it will expand freely to fill the whole of a container, having no fixed shape and no fixed volume.
Element
A substance that cannot be changed to a simpler substance by normal chemical reaction.
Periodic table
A chart of the elements arranged in order by atomic number.
Atom
The smallest quantity of an element that retains the chemical properties of the element.
Subatomic particles
A particles smaller than an atom or a cluster of such particles. (Ex. neutron proton or electron.)
Proton
Positively charged subatomic particle.
 Electron
Negatively charged subatomic particle.
Nucleus
The central region of an atom that contains the protons and neutrons.
Atomic number
 The number of protons in an atom. determines which element it is.
Mass number
The sum of a number of protons in neutrons in an atom’s nucleus.
Isotope
Alternate mass forms of an element.
Have the same number of protons and electrons but different number of neutrons.
Neutron
Electrically neutral subatomic particle.
Radioisotope
Nucleus decay spontaneously, giving off particles and energy.
Compound
Substances that contain two or more elements in a fixed ratio. (Molecules are held together by covalent bonds).
Molecule
Holds together atoms via covalent bonds.
Chemical formula
Describes a chemical composition of a substance. Ex. NaCl
Molecular formula
Actual numbers of each type of atom per molecule.
Structural formula
Arrangement of atoms in a molecule.
Chemical reaction
Process in which one or more substances, or reactants, are converted to one or more different substances, known as products.
Chemical equation
Representation of a chemical reaction using symbols of the elements to indicate the amount of substance, usually in moles, of each reactant and product.
Reactant
 Substance that participates in a chemical reaction.
Product
Substance formed by a chemical reaction.
Electron shell
Groups of orbitals of electrons with similar energies.
Orbital
Region in which electrons occur in an atom or molecule.
Valence electrons
Electrons in the outer electron shell, known as the valance shell, of an atom; in the formation of chemical bond an atom can accept electrons into its valance shell or donate or share valence electrons.
Chemical bond
Force of attraction between atoms in a compound.
Covalent bond
The chemical bond involving shared pairs of electrons; maybe single, double, or triple.
Ionic bond
The chemical attraction between a cation and an anion.
Ion
An atom group of atoms is bearing one or more units of electrical charge, either positive (cation) or negative (anion).
Cation
A positively charged ion.
Anion
A negatively charged ion.
Hydrogen bond
A weak attraction between two atoms that already participate in other chemical bonds.
Polar molecule
Molecule with an uneven distribution of charge
Solvent
 Substance capable of dissolving other substances.
Solute
A dissolved substance.
Hydration
Each ion in a solution is surrounded by oppositely charged ends of the water molecules.