CU 3rd Trimester Study Guide

Protons

A positively charged subatomic particle and has a mass of 1 AMU.

Electron

Negatively charged subatomic particle with no mass.

Neutron

Neutrally charged subatomic particle with a mass of 1 AMU.

Atomic mass - atomic number

= the number of neutrons in an atom

Atomic number

A number assigned to an element that indicates the number of protons in one atom of an element.

Nucleus

The part of the atom which contains protons and neutrons.

Alpha particle

A particle consisting of 2 protons and 2 neutrons emitted during radioactive decay.

Compounds

When two or more elements are chemically combined.

Radioactive Decay

When a radioactive element loses mass and transmutates into another element.

Atomic mass

The mass of one atom of an element.

Mixture

When two or more substances are combined but not chemically bonded.

Metals

Elements to the left of the imaginary stair step on the periodic chart that are good at conducting heat and electricity and are malleable.

Non-metals

Elements to the right of the imaginary stair step on the periodic chart that are bad conductors and are not ductile or malleable.

Metalloids

Elements touching the imaginary stair step on the periodic chart (except for aluminum) that share properties of both metals and metalloids.

Isotope

Atoms of an element with different number of neutrons.

Exothermic

Chemical reactions in which energy is given off.

Endothermic

Chemical reactions in which energy is taken in.

Nuclear fission

A nuclear reaction in which the nucleus of one atom is split into two.

Nuclear fusion

A nuclear reaction in which the nuclei of two atoms combine to form one nuclei.

Half life

The amount of time it takes for half of a radioactive isotope to transmutate into another element.

Actinides

The bottom most period of elements which are all radioactive and most are synthetic.

Lanthanides

Elements towards the bottom of the periodic chart that are soft metals that can be cut with a knife.

Product

The result of a chemical reaction.

Reactants

The two substances involved in forming a chemical reaction.

Strong nuclear force

A fundamental force responsible for holding the nuclei of atoms together.

Catalyst

A substance that starts a chemical reaction but is not changed in the chemical reaction.

Physical change

A change in which the chemical identity of a substance is not changed.

Chemical change

A change in which the chemical makeup of a substance is altered.

Law of conservation of mass

A law that states that no matter is lost or gained during a chemical reaction.

Saturated

A solution in which no more solute can dissolve.

Things that speed up chemical reactions

Catalysts

Increased surface area

Increased concentrations

Increased temperature

Acid

A solution that has a positive hydrogen ion, is corrosive to metal, and has a sour taste, and a pH less than 7.

Base

A solution that has a negative hydroxyl (OH-), is slippery when wet, tastes bitter, and is usually a good cleaner, and has a pH greater than 7.

Things that affect the solubility of a solute in a solvent

Pressure

Temperature

Type of solute

Solute

The substance in a solution that is present in a lesser quantity and gets dissolved.

Solvent

A substance in a solution that is present in a greater quantity and does the dissolving.

Neutralization

The reaction that occurs when an acid and a base are mixed with each other which results in water and a salt.

Indicator

A substance that helps determine the presence of an acid or base.

Valence electrons

Electrons on the outermost electron orbital or an atom. (Can be determined by which family the element is found in).