Atoms
What charge does an electron have?
negative
What is an element?
a pure substance that cannot be broken down by physical or chemical means
What is a column called?
group
A chemical bond is formed when electrons are shared.
covalent
the building block of matter; contains subatomic particles - neutrons, protons, and electrons
atom
What charge does a proton have?
positive
What is a compound?
a pure substance formed when 2 or more elements combine
What is a row called?
period
An _____ ______ is an electrical attraction between 2 oppositely charged atoms or groups of atoms
the center of an atom; contains neutrons and protons
nucleus
What happens to the atoms in an ionic bond?
One atom gives up electrons and one atom gains electrons
Compounds are always formed from a specific combination of elements in a _________ ratio.
fixed
Each individual block represents a different _____
element
Substances formed by ionic bonds are called _____ _____.
ionic compounds
compounds whose atoms are held together by covalent bonds
molecule
What happens to the atoms in a covalent bond?
the electrons are shared
Compounds are ______ and ______ different from the elements that comprise them.
chemically, physically
What does the periodic table allow scientists to do?
predict elements not yet discovered
An atom that has lost or gained electrons is called an ____.
ion
attractive forces between molecules
van der Waals force
What is an isotope?
a form of an element with a different number of neutrons
Compounds can be broken down by ______ processes.
chemical
The table is called periodic because elements of the same group have similar ______ and _____
chemical and physical properties
What electrons are responsible for bonding?
the outer most electrons
particle without a charge in an atom’s nucleus
neutron