CH201 - UNIT 1 ASSESSMENT

actinide

inner transition metal in the bottom of the bottom two rows of the periodic table

actinide

alkali metal

element in group 1

alkaline earth metal

element in group 2

alpha particle

positively charged particle consisting of two protons and two neutrons

anion

negatively charged atom or molecule

atomic mass

average mass of atoms of an element, expressed in amu

atomic mass unit (amu)

unit of mass equal to 1/12 of the mass of a 12C (isotope) atom, equal to Dalton

atomic number (Z)

number of protons in the nucleus of an atom

binary acid

compound that contains hydrogen and one other element, bonded in a way that imparts acidic properties to the compound (released Hydrogen cations when dissolved in water)bina

binary compound

compound containing two different elements

cation

positively charged atom or molecule

chalcogen

element in group 16ch

chemical symbol

one-, two-, or three-letter abbreviation to represent an element or its atoms

covalent bond

attractive force between the nuclei of a molecule’s atoms and pairs of electrons between the atoms

covalent compound

AKA molecular compound, composed of molecules formed by atoms of two or more different elements

electron

negatively charge, subatomic particle of relatively low mass located outside the nucleus

empirical formula

formula showing the composition of a compound given as the simplest whole-number ratio of atoms

fundamental unit of charge

equals the magnitude of the charge of an electron 1.602 × 10^-19

group

vertical column of the periodic table

halogen

element in group 17

hydrate

compound containing one or more water molecules bound within its crystals

noble gas

AKA inert gas, element in group 18

inner transition metal

element in the bottom two rowsion

ion

electrically charged atom or molecule

ionic bond

electrostatic forces of attraction between the oppositely charged ions of an ionic compound

isomers

compounds with the same chemical formula but different structures

isotopes

atoms that contain the same number of protons but different numbers of neutrons

landthanide

inner transition metal in the top of the bottom two rows of the periodic tablel

law of definite proportions

all samples of a pure compound contain the same elements in the same proportions by mass

law of multiple proportions

when two elements react to form more than one compound, a fixed mass of one element will react with masses of the other element in a ratio of small whole numbers

main group element

element in group 1,2, and 13-18

mass number (A)

sum of the number of neutrons and protons in the nucleus of an atom

metal

element that is shiny, malleable, good conductor of heat and electricity

metalloid

element that conducts heat and electricity moderately well, and possesses some properties of metals and some properties of nonmetals

molecular compound

compound composed of molecules formed by atoms of two or more elements

molecular formula

formula indicating the composition of a molecule of a compound and giving the actual # of atoms of each element in a molecule of the compound

monatomic ion

ion composed of a single atomneu

neutron

uncharged, subatomic particle located in the nucleus

nonmetal

element that appears dull, poor conductor of heat and electricity

nucleus

massive, positively charged center of an atom made up of protons and neutrons

oxyacid

compound that contains hydrogen, oxygen, and one other element, bonded in a way that imparts acidic properties to the compound

oxyanion

polyatomic anion composed of a central atom bonded to oxygen atoms

period

horizontal row of the periodic table

pnictogen

element in group 15

polyatomic ion

ion composed of more than one atom

proton

positively charged, subatomic particle located in the nucleus

representative element

main group element

spatial isomers

one of two substances that have the same molecular formula but different physical and chemical properties because their atoms are bonded differently

structural formula

shows the atoms in a molecule and how they are connectedtr

transition metal

elements in groups 3-12

aqueous solution

solution for which water is the solvent

Avogadro’s number

experimentally determined value of the number of entities comprising 1 mole of substance; 6.022 × 10²3

concentrated

qualitative term for a solution containing a solute at a relatively high concentration

dilute

qualitative term for a solution containing solute at a relatively low concentration

concentration

quantitative measure of the relative amounts of solute and solvent present in a solution

dilution

process of adding solvent to a solution in order to lower the concentration of solutes

dissolved

described the process by which solute components are dispersed in a solvent

empirical formula mass

sum of average atomic masses for all atoms represented in an empirical formula

formula mass

sum of the average masses for all atoms in a chemical formula; for covalent compounds, this is also the molecular mass

mass percentage

ratio of solute-to-solution mass expressed as a %

mass-volume percent

ratio of solute mass to solution volume, expressed as a %

molar mass

mass in grams of 1 mole of a substance

molarity (M)

unit of concentration, defined as the number of moles of solute dissolved in 1 L of solution

mole

amount of substance containing the same # of atoms, molecules, ions, or other entities as the number of atoms in exactly 12g of 12C (isotope)

parts per billion (ppb)

ratio of solute-to-solution mass multiplied by 10^9

parts per million (ppm)

ratio of solute-to-solution mass multiplied by 10^6

percent composition

percentage by mass of the various elements in a compound

solute

solution component present in a concentration less than that of the solvent

solvent

solution component present in a concentration that is higher relative to other components

volume percentage

ratio of solute-to-solution volume expressed as a percentage

Molarity equation

M = mol solute / L solution

ppm equation

(mass solute/ mass solution) x 10^6 ppm

ppb equation

(mass solute/ mass solution) x 10^9 ppb