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Chemistry of Life Vocab
Term / Definition / ExampleAtom / Smallest basic unit ofmatter. /
Element / One particular type ofatom. / Hydrogen, oxygen, carbon
Molecule / Two or more atoms held together bycovalent bonds. / O2 and H2O
Compound / Substance made of atoms of differentelements bonded together in a certainratio. / H2O
Ion / An atom that has gained or lost anelectron. / Na+ and Cl-
One is positive and one is negative
Ionic Bond / Forms between positively charged ion anda negatively chargedion. / NaCl, sodium chloride or table salt
Covalent Bond / Atoms share pairs ofelectrons. / Holds oxygen and hydrogen together in a water molecule.
Hydrogen bond / The positive charge from the hydrogen atom ofone water molecule can attract a negative chargefromanothermolecule. / Occur between water molecules.
Polar / Two atoms form a molecule using a covalentbond. having partial positive and partial negativecharges / Water
Nonpolar / Molecule which has no separation of charge, sono positive or negative poles areformed. / Oil
Cohesion / The attraction of molecules of the samesubstance. / Water forms beads or droplets
Adhesion / The attraction among molecules ofdifferent substances. / Water travels from roots to leaves in plant
Solution / Mixture of substances that is equallymixed throughout. / Kool-Aid
Solvent / Substance that there is more of, and thatdissolvesthe othersubstances. / Water
Solute / The substance that dissolves in thesolvent. / Sugar
Acid / A compound that releases a hydrogen ion. Anacid increases the concentration of H+ ions ina solution. / Lemon juice
Base / Alkaline / Removes H+ ions from a solution. After abasedissolves in water, the solution has a lowH+concentration. / Bleach
pH / Measurement of acidity; related to theconcentration of free hydrogen ions in asolution. / Scale 1-14
Monomer / One subunit of amolecule. / Glucose
Polymer / Molecule that contains many monomersbonded together. / Starch
Carbohydrates / Made of CHO, main source of energy;includessugars andstarches. / Sugars and Starches (pasta)
Lipids / Nonpolar molecule made up of CHO; includesfatsand oils. Long term energystorage. / Fats
Fatty Acids / Hydrocarbon chain often bonded to glycerol ina lipid. / Butter
Protein / Polymer made of monomers called aminoacids. / Meat, beans, nuts
Amino Acids / Contain CHONS, building blocks ofproteins(monomers). / Meat, beans, nuts
Nucleic Acids / Polymer made up of monomers callednucleotides. / DNA, RNA
Nucleotide / Monomer made up of a sugar, phosphate,and nitrogenousbase. / A, T, G, C, and U
Chemical Reaction / Change substances into different substancesby breaking and forming chemicalbonds. /
Reactants / Substances that are changed during achemical reaction. /
Products / Substances made by a chemicalreaction. /
Bond Energy / The amount of energy needed to break abond between twoatoms.
Equilibrium / When reactants and products are made at thesame rate. /
Activation Energy / The amount of energy that needs to be absorbedfora chemical reaction tostart. / See graph below.
Endothermic / Chemical reaction that absorbs more energy thanit releases. / Photosynthesis
Exothermic / Chemical reaction that releases more energy thanit absorbs. / Cellular Respiration
Catalyst / Substance that decreases the activationenergy needed to start a chemical reaction. Increaseratesofreactions. / Enzyme
Enzymes / Catalysts for chemicalreactions. Speed up processes. / Amylase
Substrate / Reactant in a chemical reaction in whichan enzymeacts. / Reactant