Reaction
Absorbs energy
What is endothermic?
H20
What is the formula for water?
The smallest unit of an element that maintains the chemical properties of an element
What is an atom?
A chemical bond formed by the electrostatic attraction between oppositely charged ions
What is an ionic bond?
The region surrounding the nucleus where electrons are most likely to be found according to modern atomic theory
What is an electron cloud?
Releases energy
What is exothermic?
Same number of atoms on both sides
What is a balanced equation?
The principle that atoms tend to gain, lose, or share electrons until they are surrounded by eight valence electrons to achieve
What is the octect rule?
A chemical bond formed when two atoms shared one or more pairs of valence electrons
What is a covalent bond?
Atoms of the same element that have the same number of protons but a different number of neutrons, resulting in different mass numbers
What is an isotope?
When atoms rearrange to create a new substance
What is a product?
Gas have no fixed _____ or shape.
What is volume?
a subatomic particle with a positive charge located in the nucleus of an atom
What is a proton?
A neutral group of two or more atoms held together by covalent bonds
What is a molecule?
The total number of protons in the nucleus of an atom which is unique to each element on the Period Table
What is the atomic number?
A substance present at the start of a chemical reaction that is consumed, altered, or rearranged to form new substances called products
What is a reactant?
Can not be separated into other materials by any physical process
What is a pure substance?
a subatomic particle with NO (neutral) charge located in the nucleus of an atom
What is a neutron?
A bond where electrons are shared unequally because one atom is more electronegative than the other
What is a polar covalent bond?
The total number of protons and neutrons added together in an atom's nucleus
What is the atomic mass?
Rusting iron
What is an example of a chemical reaction?
The type of mixture where all substances are distributed evenly.
What is a homogenous mixture?
A tiny subatomic particle with a NEGATIVE charge that moves in the space surrounding the nucleus
What is an electron?
A bond where electrons are shared equally between two atoms
What is a nonpolar covalent bond?
The small, dense positively charged center of an atom that contains protons and neutrons
What is a nucleus?