Lab Practical 1-6 Terms

clairebear2018's version from 2018-02-27 06:17

Section 1

Question Answer
precisionthe measure of the range of values of a set of measurements
accuracythe extent to which the results of a calculation or the readings of an instrument approach the true values of the calculated or measured quantities
dependent variablea variable whose value depends on that of another
independent variable a variable whose value does not depend on that of another
controlled experimenta test where the person conducting the test only changes one variable at a time in order to isolate the results
hypothesisa proposition which is assumed to be true in proving another proposition
meniscusa curved upper surface of a liquid in a tube
densitythe degree of compactness of a substance
displacementthe occupation of a submerged body or part of a body of a volume that would otherwise be occupied by a fluid
volumethe amount of space that a substance or object occupies
atomic structurethe concept of an atom as a central positively charged nucleus consisting of protons and neurons surrounded by a number of electrons
molecular structurethe type, arrangement, position and direction of the bonds linking atoms with molecules
covalent bonda bond in which each atom of a bound pair contributes one electron to form a pair of electrons
ionic bonda type of chemical bonding in which one or more electrons are transferred completely from one atom to another
hydrogen bonda weak bond between two molecules resulting from an electrostatic attraction between a proton in one molecule and an electronegative atom in the other
chemical reactiona change in which a substance is changed into one or more new substances
octet rulewhen atoms combine to share molecules they generally each lose, gain, or share valence electrons until they attain or share eight

Section 2

Question Answer
dissociationthe splitting of a molecule into smaller molecules, atoms or ions, especially by a reversible process
dissolvebecome incorporated into a liquid so as to form a solution
electrolyte a liquid or gel that contains ions and can be decomposed by electrolysis
cationpositively charged ion
anionnegatively charged ion
reactanta substance that takes part and undergoes change during a reaction
producta substance formed as a result of a chemical reaction
molestandard scientific unit for measuring large quantities of very small entities such as atoms, molecules or other specified particals. 6.022 x 10^23
molaritythe number of moles of solute divided by the number of liters of solution
molecular formulathe number of atoms of each of the elements present in one molecule of a specific compound
molecular massa number equal to the sum of the atomic masses of the atoms in a molecule
solventable to dissolve other substances
solutesubstance that is dissolved in a solution
solutiona liquid mixture in which the solute is uniformly distributed within the solvent
standard curverepresents the relationship between two quantities, used to determine the value of an unknown quantity from one that is more easily measured

Section 3

Question Answer
absorbancethe measure of the capacity of a substance to absorb light of a specified wavelength
pHmeasure of hydrogen ion concentration ; measure of acidity or alkalinity of a solution
buffera solution that resists change in pH when acid or alkali is adder to it
acida chemical substance that neutralizes alkalis, pH less than 7
basea substance capable of reacting with an acid to form a salt and water, or of accepting or neutralizing hydrogen ions
acidic solutionany solution that has a higher concentration of hydrogen ions than water
basic solutionan aqueous solution containing more OH- ions than H+ ions. An aqueous solution with a pH greater than 7
monomera molecule that can be bonded to other identical molecules to form a polymer
macromoleculea molecule containing a very large number of atoms such as a protein, nucleic acid or synthetic polymer
polymera substance that has a molecular structure consisting chiefly or entirely of a large number of similar units bonded together
bradford reagentcan be used to determine the concentration of proteins in a solution