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
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
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
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
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
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
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
what is the normal melting point of the pure substance Z? - Correct Answer 4 degrees celsius
-where 760 mm Hg the melting point curve ( line between solid and liquid) lies at approximately at 4
degrees celsius)
if it were to ask boiling point you would see what the temperature was at 760 mm Hg for the boiling
point curve (line between liquid and gas)
which substance meets the requirements: cubic solid, poor electrical conductor in solid state, good
conductor when fused - Correct Answer NaCl
ionic bonding; crystalline structure; low conductivity when solid; high conductivity when fused
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
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
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
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
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
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
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
what is the normal melting point of the pure substance Z? - Correct Answer 4 degrees celsius
-where 760 mm Hg the melting point curve ( line between solid and liquid) lies at approximately at 4
degrees celsius)
if it were to ask boiling point you would see what the temperature was at 760 mm Hg for the boiling
point curve (line between liquid and gas)
which substance meets the requirements: cubic solid, poor electrical conductor in solid state, good
conductor when fused - Correct Answer NaCl
ionic bonding; crystalline structure; low conductivity when solid; high conductivity when fused
