Chapter 2 Vocab

Atom

Basic unit of matter

Nucleus

Structure that contains a cell’s DNA

Electron

Negatively charged particle surrounding the nucleus

Element

Pure substance that consists entirely of one element

Isotope

One of several forms of a single element

Compound

Substance formed by the chemical combination of two or more elements

Ionic Bond

Chemical bond formed when one or more electrons are transferred from one atom to another

Ion

Atom that has a positive or negative charge

Covalent Bond

Type of bond in which electrons between atoms are shared

Molecule

Smallest unit of most compounds that displays all the properties of that compound

Van oer Waals forces

Slight attraction that develops between oppositely charged regions of nearby molecules

Hydrogen Bond

Weak attraction between a hydrogen atom and another atom

Cohesion

Attraction between molecules of the same substance

Adhesion

Attraction between different kinds of molecules

Mixture

Material composed of two or more elements or compounds that are physically mixed together but not chemically combined

Solution

Type of mixture in which all the components are evenly distributed

Solute

Substance that is dissolved in a solution

Solvent

Dissolving substance in a solution

Suspension

Mixture of water and non-dissolved material

pH Scale

Scale with values from 0 to 14 used to measure the concentration of H+ ions in a solution. pH of 0 to 7 is acidic, 7 is neutral, and 7 to 14 is base

Acid

A compound that forms hydrogen ions in solution; pH less that 7

Base

A compound that produces hydroxide ions in solution; pH of more than 7

Buffer

A compound that prevents sharp, sudden change in pH