8th Gr Science - Chemistry Concepts
Terms in this set (31)
Anything that has volume or mass.
The smallest unit of an element that has all of the properties of that element containing a nucleus within an electron cloud.
The tiny, very dense, positively charged region in the center of an atom; made up of protons and neutrons.
All of the area inside an atom surrounding the nucleus where electrons are found.
A form of charge, designated negative, positive, or neutral (without charge) that is found on the subatomic particles that make up all atoms.
A positively charged subatomic particle of the nucleus of an atom that contributes to the mass of the atom.
A subatomic particle of the nucleus of an atom that is without charge that contributes to the mass of an atom.
A negatively charged subatomic particle of the electron cloud that is involved in the formation of chemical bonds.
Particles that are smaller than the atom, such as Neutrons, Protons, and Electrons.
Chemical reactions in which both side of the equation contain equal numbers of atoms of each element. The mass and the charge must be balanced on both sides of the reaction.
The number of protons and neutrons in an element.
Is a bond that forms when electrons (e-) are transerred from one atom to another.
*****This leaves both elements with a charge, 1 positive and 1 negetive.
Ions are created when an atom either loses or gains an electron.
Are formed when an atom gains an electron.
A number below and to the right of a chemical symbol that indicates the number of atoms in a molecule.
A number to the left of a chemical symbol that multiplys the number of atoms in a molecule.
The smallest unit of a substance that keeps all of it's physical and chemical properties.
A bond formed when atoms share one or more pair of electrons
a POSITIVE ion
a NEGETIVE ion
(you can remember this by using this):
The combining of atoms to form molecules or ionic compounds.
An electron that is found in the outermost shell of an atom an determines the chemical properties of the atom.
What is needed to break bonds?
_________ energy is a part of all reactions.
Energy is released in these reactions. The energy can be released as:
*The higher the temperature the faster the reaction proceeds.
**REASON: Particles move faster when heated.
***Particles collide more often and with more energy.
The higher the concentration, the faster the reaction.
~~REASON: Smaller distance between particles, they collide more often.
*The amount of exposed suface
**Increasing Surface Area means faster reaction
***EXAMPLE: Crushing a solid into a powder increases rate of reaction.
Presence of INHIBITOR or CATALYST
*INHIBITORS-slow down or STOP reactions.
**CATALYSTS-lower the activation energy and makes reactions go faster.
Factors affeting the "Rates Of Reaction"
*Presence Of Inhibitor OR Catalyst
Are labeled based on the number of electrons lost.