Term | Definition |
Matter | Anything that occupies space and has mass |
Mass | the quantity of matter an object has. |
Atom | The simplest particle of an element that retains all of the properties of that element |
Nucleus | The central region of an atom |
Proton | A positively charged subatomic particle |
Atomic Number | The number of protons in an atom |
Mass Number | an atom is equal is equal to the total number of protons and neutrons in an atom. |
Electrons | high-energy particles that have very little mass |
Orbital | a three-dimensional region around a nucleus that indicates the probable location of an electron. |
Isotopes | Atoms of the same element that have a different numbers of neutrons |
Chemical Bond | the attractive forces that hold atoms together |
Covalent Bond | when two atoms share one or more pairs of electrons |
Molecule | the simplest part of a substance that retains all of the properties of that substance and can exist in a free state. |
Ion | An atom or molecule with electrical charge |
Ionic Bond | Positive and negative electrical charges attract each each other, the sodium ion and the chloride ion attract each other |
Energy | the ability to do work |
Chemical Reaction | one or more substance charge to produce one or more different substances |
Reactants | shown on the left side of the equation (before arrow) |
Products | this reaction are shown on the right side (after the arrow) |
Metabolism | the term used to describe all of the chemicals reaction that occur in an organism |
Activation Energy | the amount of energy needed to start a chemical reaction |
Catalysts | reduced the amount of activation energy that is needed for a reaction to take place |
Enzyme | a protein or RNA molecule that speed that speeds up metabolic reactions without being permanently changed or destroyed |
Redox reaction | when electrons are transferred between atoms are known as oxidation reduction reactions or |
Oxidation Reactions | a reactant loses one or more electrons, thus becoming more positive in charge |
Reduction reaction | a reactant gains on or more election thus becoming more negative in charge |
Polar | Uneven distribution of charge |
Hydrogen Bond | the force of attraction between a hydrogen molecule with a partial positive charge and another atom molecule with a or full negative charge |
Cohesion | An attractive force that holds molecules of a single substance together |
Adhesion | the attractive force between two particles of different substances (ex. water molecules and glass molecules) |
Capillarity | the attraction between molecules that results in the rise of the surface of a liquid when in contact with solid |
Solution | a mixture in which one or more substances are uniformly distributed in another substance. |
Solute | a substance dissolved in the solvent |
Solvent | the substance in which the solute is dissolved |
Concentration | the amount of solute dissolved in a fixed amount of of the solution |
Saturated Solution | one in which o more solute can dissolve |
Aqueous Solution | solutions in which water is the solvent |
Hydroxide Ion | OH- ion |
Hydronium Ion | H3O + ion |
Base | A solution that contains more hydroxide ions than hydronium ions |
pH scale | A scale for comparing the relative concentrations of hydronium ions and hydroxide ions in a solution |
Buffers | chemical substances that neutralize small amounts of either acid or base added to a solution |