WGU D425 INTRO TO CHEMISTRY
OBJECTIVE ASSESSMENT 2025/2026 |
COMPLETE QUESTIONS AND ANSWERS
WITH RATIONALES | 100% VERIFIED
<RECENT VERSION >
Electron - ANSWER A subatomic particle that has a negative charge
significant figures - ANSWER a prescribed decimal place that determines the
amount of rounding off to be done based on the precision of the measurement
mass number - ANSWER the sum of the number of neutrons and protons in an
atomic nucleus
amu - ANSWER atomic mass unit
average atomic mass formula - ANSWER (mass)(%)+(mass)(%)/100 ( % in
decimal)
atomic radius - ANSWER the distance from the center of an atom's nucleus to
its outermost electron
,Energy level 1 holds how many electrons? - ANSWER up to 2 electrons
Energy level 2 holds how many electrons? - ANSWER up to 8 electrons
Energy level 3 holds how many electrons? - ANSWER up to 18 electrons
Lewis Dot Structure - ANSWER diagram of a molecule using dots to represent
valence electrons
polyatomic ions - ANSWER groups of atoms with an overall charge
Functional groups - ANSWER the components of organic molecules that are
most commonly involved in chemical reactions
Alkane - ANSWER a hydrocarbon containing only single covalent bonds
Alkyne - ANSWER carbon-carbon triple bond
Alkene - ANSWER double bond, carbon to carbon.
Avogadro's number - ANSWER 6.02 x 10^23, the number of atoms or
molecules in 1 mol
, molar mass - ANSWER the mass of one mole of a pure substance 1:1 ratio with
atomic mass, in g/mol
PV=nRT - ANSWER ideal gas law equation
molar volume - ANSWER the volume occupied by 1 mole of a gas at standard
temperature and pressure (STP); 22.4 L
Any gas at STP has the volume of... - ANSWER 22.4L
double replacement reaction - ANSWER a chemical change that involves an
exchange of positive ions between two compounds
redox reaction - ANSWER A chemical reaction involving the transfer of one or
more electrons from one reactant to another; also called oxidation-reduction
reaction.
precipitation reaction - ANSWER The formation of a solid from a solution
during a chemical reaction. Precipitates are often formed when two aqueous
solutions are mixed together.
mole to mole ratio - ANSWER A ratio made from the coefficient in a chemical
equation (or from the subscripts in a chemical formula).
homogeneous mixture - ANSWER A mixture in which substances are evenly
distributed throughout the mixture
, heterogeneous mixture - ANSWER A mixture in which different materials can
be distinguished easily
1 mole expressed in scientific notation - ANSWER 6.022X10^23
CN- - ANSWER Cyanide
HCl - ANSWER hydrochloric acid
C2H302- - ANSWER Acetate
NH4+ - ANSWER Ammonium
CO32- - ANSWER Carbonate
ClO3- - ANSWER Chlorate
ClO2- - ANSWER Chlorite
PO43- - ANSWER Phosphate
OH- - ANSWER Hydroxide
OBJECTIVE ASSESSMENT 2025/2026 |
COMPLETE QUESTIONS AND ANSWERS
WITH RATIONALES | 100% VERIFIED
<RECENT VERSION >
Electron - ANSWER A subatomic particle that has a negative charge
significant figures - ANSWER a prescribed decimal place that determines the
amount of rounding off to be done based on the precision of the measurement
mass number - ANSWER the sum of the number of neutrons and protons in an
atomic nucleus
amu - ANSWER atomic mass unit
average atomic mass formula - ANSWER (mass)(%)+(mass)(%)/100 ( % in
decimal)
atomic radius - ANSWER the distance from the center of an atom's nucleus to
its outermost electron
,Energy level 1 holds how many electrons? - ANSWER up to 2 electrons
Energy level 2 holds how many electrons? - ANSWER up to 8 electrons
Energy level 3 holds how many electrons? - ANSWER up to 18 electrons
Lewis Dot Structure - ANSWER diagram of a molecule using dots to represent
valence electrons
polyatomic ions - ANSWER groups of atoms with an overall charge
Functional groups - ANSWER the components of organic molecules that are
most commonly involved in chemical reactions
Alkane - ANSWER a hydrocarbon containing only single covalent bonds
Alkyne - ANSWER carbon-carbon triple bond
Alkene - ANSWER double bond, carbon to carbon.
Avogadro's number - ANSWER 6.02 x 10^23, the number of atoms or
molecules in 1 mol
, molar mass - ANSWER the mass of one mole of a pure substance 1:1 ratio with
atomic mass, in g/mol
PV=nRT - ANSWER ideal gas law equation
molar volume - ANSWER the volume occupied by 1 mole of a gas at standard
temperature and pressure (STP); 22.4 L
Any gas at STP has the volume of... - ANSWER 22.4L
double replacement reaction - ANSWER a chemical change that involves an
exchange of positive ions between two compounds
redox reaction - ANSWER A chemical reaction involving the transfer of one or
more electrons from one reactant to another; also called oxidation-reduction
reaction.
precipitation reaction - ANSWER The formation of a solid from a solution
during a chemical reaction. Precipitates are often formed when two aqueous
solutions are mixed together.
mole to mole ratio - ANSWER A ratio made from the coefficient in a chemical
equation (or from the subscripts in a chemical formula).
homogeneous mixture - ANSWER A mixture in which substances are evenly
distributed throughout the mixture
, heterogeneous mixture - ANSWER A mixture in which different materials can
be distinguished easily
1 mole expressed in scientific notation - ANSWER 6.022X10^23
CN- - ANSWER Cyanide
HCl - ANSWER hydrochloric acid
C2H302- - ANSWER Acetate
NH4+ - ANSWER Ammonium
CO32- - ANSWER Carbonate
ClO3- - ANSWER Chlorate
ClO2- - ANSWER Chlorite
PO43- - ANSWER Phosphate
OH- - ANSWER Hydroxide
