Atoms
Which group of elements contains a stable level of outer electrons for each element?
noble gases
a characteristic of something that can be observed without changing the essence of the object is called what?
physical property
matter with no definite volume or shape is known as what?
a gas
What do we call the things on the left hand, or starting, side of a chemical reaction.
reactants
What type of compound has water attached to it?
a hydrate
the smallest piece of an element that still retains the properties of an element is known as what?
an atom, atom
A change from one substance to another is what type of change?
chemical
the most common state of matter in the universe is what?
plasma
What can we use to represent a chemical reaction using symbols and formulas?
a chemical equation
Dot diagrams are used to represent what?
valence electrons, outer electrons
What type of ion has more than one atom?
complex ion
a change in size, shape, or state of matter is what type of change?
physical
liquid
a chemical reaction that combines two or more substances into another is known as what type?
synthesis reaction
how many atoms are in binary compounds?
two
what do we call the force that holds atoms together in a compound?
a bond, bond
burning a log would be what type of change?
chemical change
What do we call the temperature where a solid begins to liquify?
melting point
What do we call the substance that speeds up chemical reactions without changing ITS individual properties or composition?
catalyst, a catalyst
What number describes the number of protons in the nucleus of an atom?
atomic number
How many atoms are generally needed in the outer energy level of an atom for it to be stable?
8
The amount of energy needed to change a material from a liquid to a gas is the _____ ___ _________.
heat of vaporization
the process that involves a solid turning directly into a gas without any intermediate stage is known as what?
sublimation
What do we call the energy needed to start a chemical reaction?
activation energy
Atoms of the same element that have differing numbers of neutrons can be called what?
Isotopes