Question | Answer |
atom | the smallest basic unit of matter |
element | one particular type of atom that cannot be broken down into a simpler substance |
compound | a substance made of atoms of different elements bonded together in a certain ratio |
ion | an atom that has gained or lost one or more electrons |
ionic bond | a chemical bond between atoms formed through the electrical force between oppositely charged ions |
covalent bond | a chemical bond that involves the sharing of electron pairs between atoms |
molecule | two or more atoms held together by covalent bonds |
hydrogen bond | an attraction between a slightly positive hydrogen atom and a slightly negative atom (often oxygen or nitrogen) |
cohesion | the attraction among molecules of the same substance |
adhesion | the attraction among molecules of different substances |
solution | a mixture of substances that is the same throughout (homogeneous mixture) |
solvent | the substance that dissolves another substance; the substance that is present in the greater amount in a solution |
solute | a substance that is dissolved; present in a smaller amount in a solution |
acid | a compound that releases a proton (hydrogen ion) when is dissolves in water; has a pH lower than 7 |
base | a compound that removes hydrogen ions from a solution; has a pH higher than 7 |
pH | the measurement of a concentration's acidity |
monomer | a single subunit in a complete molecule |
polymer | a large molecule (or macromolecule) made of many monomers bonded together |
carbohydrate | - sugars and starches |
- carbon, hydrogen, oxygen | |
- Monomer =monosaccharide | |
- quick energy; some storage | |
- 2:1 ratio of hydrogen to oxygen; one sugar - monosaccharide; two sugars - disaccharide; many sugars - polysaccharide | |
- test: benedict's reagent | |
lipid | Name: fats, oil, waxes |
Elements: carbon, hydrogen, oxygen | |
Monomer: glycerol and 3 fatty acids | |
Functions: storage, energy reserves, cell membranes | |
Other Facts: insoluble in water, shaped life an elongated E | |
Test: paper bag test | |
fatty acids | chains of carbon atoms bonded to hydrogen atoms |
protein | Elements: carbon, hydrogen, oxygen, nitrogen |
Monomer: amino acid | |
Functions: basic building blocks or living material; hair, muscles, fingernails; enzymes (speed up chemical reactions); transport in cell | |
amino acids | molecules that contain carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur |
nucleic acids | polymers that are made up of monomers called nucleotides |
chemical reaction | a reaction that changes substances into other substances by breaking and forming chemical bonds |
reactant | the substance changed during a chemical reaction |
product | the substance made by a chemical reaction |
bond energy | the amount of energy that will break a bond between two atoms |
equilibrium | the state that is reached when bother the reactants and products are made at the same rate |
activation energy | the amount of energy that needs to be absorbed for a chemical reaction to start |
exothermic | the type of chemical reaction that releases more energy than is absorbs |
endothermic | the type of chemical reaction that absorbs more energy than it releases |
catalyst | a substance that decreases the activation energy needed to start a chemical reaction and also increases the rate of the chemical reaction |
enzyme | the catalyst for chemical reactions in living things |
substrate | the specific reactant that an enzyme acts on |
inorganic compounds | compounds that are not made by living things |
organic compounds | carbon compounds made by living things; form covalent bonds |
macromolecules | built by linking a set of building blocks (monomers) together into long chains (a polymer) |
monomers | basic units that repeat over and over in organic compounds |
polymers | made up of many, many molecules all strung together to form really long chains (and sometimes more complicated structures) |