ACS GEN CHEM 2 EXAM REVIEW QUESTIONS AND ANSWERS |
FALL 2025/2026 UPDATE | 100% CORRECT
Question 1
which particle, if lost from the nucleus will not result in a change in the atomic number?
Correct Answer
PROTON - one unit of positive charge
ALPHA PARTICLE - has two units of positive charge
BETA PARTICLE - one unit of negative charge
NEUTRON - has no charge, and will not change the atomic number
Question 2
an atom of the element of atomic number 84 and mass number 199 emits an alpha particle. the residual atom after this
change has an atomic number of _______ and a mass number of _______.
Correct Answer
when an atom emits an alpha it looses 2 protons and 2 neutrons
So atomic number Z which represents the number of protons is decreased by 2 : here 84-2 =82
and The mass number A which represents number of protons + neutrons is dereassed by 4: here 199-4= 195
side note: beta particles result in gain of one proton and loss of one neutron, so mass stays the same and atomic number
increases by one
Page 1 of 24
,Question 3
in effecting nuclear changes by bombarding target nuclei with positively charged alpha particles it is necessary to
accelerate these particles to high speed because it is necessary to
Correct Answer
overcome the force of repulsion of the nucleus
Question 4
a simple method of showing experimentally that a solid substance may be ionic is to show that it
Correct Answer
conducts electricity in when dissolved in water
-unique to ionic compounds
Question 5
the boiling point of water compared with other members of the series can be explained by:
Correct Answer
hydrogen bonding
-has the highest IMF than the other compounds listed due to h bond. h bonds only happen when H is bonded to N, O, or
F
Page 2 of 24
, Question 6
sodium chloride NaCl crystallizes in a face centered cubic lattice of chloride ions, with smaller sodium ions occupying holes
between Cl ions. how many cl- ions are in contact with and single Na+ ion
Correct Answer
6
-is a octahedral hole - so coordination number of 6; tetrahedral have coordination number of 4 and simple cubic hole has
coordination number of 8
Question 7
according to the phase diagram showing the gas, liquid and solid phases of a pure substance what phase or phases can be
present at point x (phase diagram where x lies on boiling point curve)
Correct Answer
liquid and gas
-know where each state lies on diagram
three phases are always in same relative positions with varying slopes. if point lies on the phase boundary line both
phases can occur together
Page 3 of 24
FALL 2025/2026 UPDATE | 100% CORRECT
Question 1
which particle, if lost from the nucleus will not result in a change in the atomic number?
Correct Answer
PROTON - one unit of positive charge
ALPHA PARTICLE - has two units of positive charge
BETA PARTICLE - one unit of negative charge
NEUTRON - has no charge, and will not change the atomic number
Question 2
an atom of the element of atomic number 84 and mass number 199 emits an alpha particle. the residual atom after this
change has an atomic number of _______ and a mass number of _______.
Correct Answer
when an atom emits an alpha it looses 2 protons and 2 neutrons
So atomic number Z which represents the number of protons is decreased by 2 : here 84-2 =82
and The mass number A which represents number of protons + neutrons is dereassed by 4: here 199-4= 195
side note: beta particles result in gain of one proton and loss of one neutron, so mass stays the same and atomic number
increases by one
Page 1 of 24
,Question 3
in effecting nuclear changes by bombarding target nuclei with positively charged alpha particles it is necessary to
accelerate these particles to high speed because it is necessary to
Correct Answer
overcome the force of repulsion of the nucleus
Question 4
a simple method of showing experimentally that a solid substance may be ionic is to show that it
Correct Answer
conducts electricity in when dissolved in water
-unique to ionic compounds
Question 5
the boiling point of water compared with other members of the series can be explained by:
Correct Answer
hydrogen bonding
-has the highest IMF than the other compounds listed due to h bond. h bonds only happen when H is bonded to N, O, or
F
Page 2 of 24
, Question 6
sodium chloride NaCl crystallizes in a face centered cubic lattice of chloride ions, with smaller sodium ions occupying holes
between Cl ions. how many cl- ions are in contact with and single Na+ ion
Correct Answer
6
-is a octahedral hole - so coordination number of 6; tetrahedral have coordination number of 4 and simple cubic hole has
coordination number of 8
Question 7
according to the phase diagram showing the gas, liquid and solid phases of a pure substance what phase or phases can be
present at point x (phase diagram where x lies on boiling point curve)
Correct Answer
liquid and gas
-know where each state lies on diagram
three phases are always in same relative positions with varying slopes. if point lies on the phase boundary line both
phases can occur together
Page 3 of 24
