Chemistry Exam 1 Northeastern University Questions With
Complete Solutions
A mass spectrometer determines correct answers relative
masses of atoms and the percent of each isotope of an element
acetate correct answers C2H3O2(-)
ammonium correct answers NH4(+)
An element has two different isotopes: one weighs 65 amu and
another weighs 67 amu. If the average atomic mass of all the
isotopes is 66.5amu, what can be said about the relative
abundance of the isotopes? correct answers The isotope with the
mass of 67 is more abundant than the isotope with the mass of
65 because the average amu is closer to 67 than 65
Anion correct answers a negatively charged ion
Atomic Radius correct answers The distance from the center of
the nucleus to the outermost electrons.
~Increases down the group
~Decreases from left to right
aurbau principle correct answers sublevels are filled in order of
increasing energy
Bohr's theory correct answers His theory was that the electrons
of a particular atom are restricted to specific "Orbits" or
"Shells." The farther away an electron is from the nucleus, the
, more energy it can emit. However, electrons only emit or absorb
energy when they jump from shell to shell.
carbonate correct answers CO3(2-)
Cation correct answers a positively charged ion
Chemical Change correct answers the composition of matter
changes e.g. burning wax, boiling eggs
Chemical properties correct answers observed by changing
chemical identity e.g. flammability
chlorate correct answers ClO3(-)
chlorite correct answers ClO2(-)
chromate correct answers CrO4(2-)
chromatography correct answers separates liquid-liquid mixture
of different solubilities in a medium
Cobalt has how many unpaired electrons? correct answers The
only partially filled subshell is the 3d
Covalent bonds are more likely to form when correct answers
on that is composed of only non-metals
cyanide correct answers CN(-)
Complete Solutions
A mass spectrometer determines correct answers relative
masses of atoms and the percent of each isotope of an element
acetate correct answers C2H3O2(-)
ammonium correct answers NH4(+)
An element has two different isotopes: one weighs 65 amu and
another weighs 67 amu. If the average atomic mass of all the
isotopes is 66.5amu, what can be said about the relative
abundance of the isotopes? correct answers The isotope with the
mass of 67 is more abundant than the isotope with the mass of
65 because the average amu is closer to 67 than 65
Anion correct answers a negatively charged ion
Atomic Radius correct answers The distance from the center of
the nucleus to the outermost electrons.
~Increases down the group
~Decreases from left to right
aurbau principle correct answers sublevels are filled in order of
increasing energy
Bohr's theory correct answers His theory was that the electrons
of a particular atom are restricted to specific "Orbits" or
"Shells." The farther away an electron is from the nucleus, the
, more energy it can emit. However, electrons only emit or absorb
energy when they jump from shell to shell.
carbonate correct answers CO3(2-)
Cation correct answers a positively charged ion
Chemical Change correct answers the composition of matter
changes e.g. burning wax, boiling eggs
Chemical properties correct answers observed by changing
chemical identity e.g. flammability
chlorate correct answers ClO3(-)
chlorite correct answers ClO2(-)
chromate correct answers CrO4(2-)
chromatography correct answers separates liquid-liquid mixture
of different solubilities in a medium
Cobalt has how many unpaired electrons? correct answers The
only partially filled subshell is the 3d
Covalent bonds are more likely to form when correct answers
on that is composed of only non-metals
cyanide correct answers CN(-)
