IEB definitions: Chemistry

Question 1

molar mass

Answer 1

mass in grams of one mole of substance

Question 2

solution

Answer 2

a homogeneous mixture of solute and solvent

Question 3

solute

Answer 3

substance that is dissolved in a solution

Question 4

solvent

Answer 4

the substance in which another substance is dissolved forming a solution

Question 5

concentration

Answer 5

number of moles of solute per unit volume of solution

Question 6

standard solution

Answer 6

solution of known concentration

Question 7

yield

Answer 7

measure of the extent of a reaction generally measured by comparing the amount of product against the amount of product possible

Question 8

intramolecular bond

Answer 8

occurs between atoms within molecules

Question 9

electronegativity

Answer 9

measure of the tendency of an atom to attract a bonding pair of electrons

Question 10

covalent bond

Answer 10

a sharing of at least one pair of electrons by two atoms

Question 11

non polar covalent (pure covalent)

Answer 11

an equal sharing of electrons

Question 12

polar covalent

Answer 12

unequal sharing of electrons leading to a dipole forming (as a result of electro negativity difference)

Question 13

iconic bond

Answer 13

the transfer of electrons and subsequent electrostatic attraction

Question 14

metallic bonding

Answer 14

occurs between a positive _kernel and a sea of delocalized electrons

Question 15

intermolecular force

Answer 15

a weak force of attraction between molecules or between atoms of noble gasses

Question 16

heat of reaction ( delta H)

Answer 16

the net change of chemical potential energy of the system

Question 17

exothermic reactions

Answer 17

reactions which transform chemical potential energy into thermal energy

Question 18

endothermic reactions

Answer 18

reactions which transform thermal energy into chemical potential energy

Question 19

activation energy

Answer 19

minimum amount of energy required to start a chemical reaction or the energy required to form the activated complex

Question 20

activated complex

Answer 20

high energy, unstable, temporary transition state between the reactants and the products

Question 21

reaction rate

Answer 21

change in concentration per unit of time of either a reactant or product

Question 22

catalyst

Answer 22

a substance that increases the rate of the reaction but remains unchanged at the end of the reaction

Question 23

functional group

Answer 23

an atom or group of atoms that form the center of chemical activity in the molecule

Question 24

hydrocarbon

Answer 24

compound containing only carbon and hydrogen atoms

Question 25

homologous series

Answer 25

a series of similar compounds which have the same functional group and have the same general formula in which each member differs from the previous one by a single CH2 unit

Question 26

saturated compound

Answer 26

a compound in which all of the bonds between carbon atoms are single bonds

Question 27

unsaturated compound

Answer 27

compound in which there is at least one double and/or triple bond between carbon atoms

Question 28

isomers

Answer 28

compounds having the same molecular formula but different structural formulae