Chapter 2 Flashcards
Kinetic Energy
Energy of motion
Energy
The ability to do work
Potential Energy
Inactive, stored energy
Chemical Energy
Energy form stored in chemical bonds
Electrical Energy
Energy firm resulting from the movement of charged particles
Mechanical Energy
Energy form directly involved in putting matter into motion
Radiant energy
Energy of the electromagnetic spectrum, which includes heat, light, ultraviolet waves, infrared waves, and other forms
Elements
Any of the building blocks of matter; oxygen, hydrogen, carbon for example
Atoms
The smallest part of an element; indivisible by ordinary chemical means
Atomic symbol
A one/two letter symbol indicating a particular element
Protons
Subatomic particle that bears a positive charge; located in the atomic nucleus
Neutrons
Uncharged subatomic particles; found in the atomic nucleus
Electrons
Negatively charged subatomic particle; orbits the atomic nucleus
Atomic number
The number of protons in an atom
Atomic Mass
The sum of the number of protons and neutrons in the nucleus of an atom
Atomic Weight
Average of the mass numbers of all the isotopes of an element
Isotopes
Different atomic form of the same element. Isotopes vary only on the number of neutrons they contain
Radioisotope
Isotope that exhibits radioactive behavior
Radioactivity
The process of spontaneous decay seen in some of the heavier isotopes, during which particles or energy is emitted from the atomic nucleus; results in the atom becoming more stable
Molecules
Particle consisting of two or more atoms held together by chemical bonds
Compound
Substance composed of two or more different elements, the atoms of which are chemically united
Chemical Reaction
Process in which molecules are formed, changed, or broken down
Valence Shell
The outermost energy level of an atom that contains electrons; the electrons in the valence shell determine the bonding behavior of the atom
Ionic Bond
Bond formed by the complete transfer of electrons from one atom to another. The resulting charged atoms, or ions, are oppositely charged and attract each other
Ion
An atom with a positive or negative electric charge
Salts
Ionic compound that dissociates into charged particles (other than hydrogen or hydroxyl ions) when dissolved in water
Covalent Bonds
A bond involving the sharing of electrons between atoms
Hydrogen Bond
Weak bond in which a hydrogen atom forms a bridge between two electron-hungry atoms. An important intermolecular bond
Synthesis Reactions
Chemical reaction in which larger molecules are formed from simpler ones
Decomposition Reaction
A destructive chemical reaction in which complex substances are broken down into simpler ones
Exchange Reactions
A chemical reaction in which bonds are both made and broken; atoms become combined with different atoms
Inorganic Compounds
A compound that lacks carbon; for example, water
Organic Compounds
A compound containing carbon; examples include proteins, carbohydrates, and fats
Salt
Ionic compound that dissociates into charged particles (other than hydrogen or hydroxyl ions) when dissolved in water
Electrolytes
A substance that breaks down into ions when in solution and is capable of conducting an electric current
Acids
A substance that liberates hydrogen ions when in an aqueous solution; compare with base
Bases
A substance that accepts hydrogen ions; proton acceptor; compare with acid
Neutralization
A chemical reaction that occurs between an acid and a base
pH
The symbol for hydrogen ion concentration; a measure of the relative acidity or alkalinity of a solution
Buffer
A substance or substances that help to stabilize the pH if a solution
Dehydration Synthesis
Process by which a larger molecule is synthesized from smaller ones by removal of a water molecule at each site of bond formation
Hydrolysis
The process in which water is used to split a substance into smaller particles
Carbohydrates
Organic compound composed of carbon, hydrogen, and oxygen; includes starches, sugars, cellulose
Monosaccharide
Literally, one sugar; the building block of carbohydrates; examples include glucose and fructose
Glucose
The principal sugar in the blood; a monosaccharide
Disaccharide
Literally, double sugar; examples include sucrose and lactose
Polysaccharide
Literally, many sugars; a polymer of linked monosaccharides; examples include starch and glycogen
Lipids
Organic compound formed of carbon, hydrogen, and oxygen; examples include fats and cholesterol
Triglycerides
Compounds composed of fatty acids and glycerol; fats and oils; also called neutral fats
Fatty Acids
A building block of fat
Glycerol
A sugar alcohol; one of the building blocks of fat
Steroids
A specific group of chemical substances including certain hormones and cholesterol
Cholesterol
A steroid function found in animal fats as well as in most body tissues; made by the liver
Proteins
A complex nitrogenous substance; the main building material of cells
Amino acids
An organic compound containing nitrogen, carbon, hydrogen, and oxygen; the building block of protein
Globular Proteins
A protein whose functional structure is basically spherical. Also referred to as functional protein; includes hemoglobin, enzymes, and some hormones
Enzymes
A substance formed by living cells that acts as a catalyst in chemical reactions in the body
Nucleic Acid
Class of organic molecules that includes DNA & RNA
Nucleotides
Building block of nucleic acids
Deoxyribonucleic acid (DNA)
Nucleic acid found in all living cells; carries the organisms hereditary information
Ribonucleic acid (RNA)
The nucleic acid that contains ribose; acts in protein synthesis
Adenosine triphosphate (ATP)
The compound that is the important intercellular energy source; cellular energy
