AS CHEMISTRY EXAM TOPIC 1
(QUESTIONS AND CORRECT
ANSWERS)) STUDY NOW
Explain why the second ionisation energy of boron is higher than the first ionisation
energy of boron.[1] -CORRECT ANSWER electron being removed from a positive ion
therefore needs more energy/ electron being removed is closer to the nucleus.
Give two reasons why the sample must be ionised in mass spectrometer.[2] -
CORRECT ANSWER 1. to deflect
2. to accelerate
why is the first ionisation energy of krypton greater than that of bromine?[2] -CORRECT
ANSWER Krypton has more protons than bromine
but its outer electrons are in the same shell.
why is the first ionisation energy of aluminium less than the first ionisation energy of
magnesium.[2] -CORRECT ANSWER Al outer electron in 3p orbital and Mg outer
electron in 3s
energy of 3p is greater than 3s
State how the relative molecular mass of a covalent compound is obtained from its
mass spectrum.[1] -CORRECT ANSWER Mr = highest m/z value 1
State the block in the Periodic Table in which sulphur is placed and explain your
CORRECT ANSWER.[2] -CORRECT ANSWER p
outer orbital is 3p
State the relative charge and relative mass of a proton, of a neutron and of an electron.
In terms of particles, explain the relationship between two isotopes of the same
element.
Explain why these isotopes have identical chemical properties.[7] -CORRECT
ANSWER proton:mass 1 charge +1
neutron:mass 1 charge 0
electron: mass 1/1840 charge -1
isotopes have the same number of protons but a different number of neutrons.
isotopes have the same electronic configuration
chemical properties depend on electrons
Define the term relative atomic mass. An element exists as a mixture of three isotopes.
Explain, in detail, how the relative atomic mass of this element can be calculated from
data obtained from the mass spectrum of the element. [7] -CORRECT ANSWER -
weighted average mass of an element compared to 1/12 of an atom of carbon 12.
-spectrum gives relative abundance
(QUESTIONS AND CORRECT
ANSWERS)) STUDY NOW
Explain why the second ionisation energy of boron is higher than the first ionisation
energy of boron.[1] -CORRECT ANSWER electron being removed from a positive ion
therefore needs more energy/ electron being removed is closer to the nucleus.
Give two reasons why the sample must be ionised in mass spectrometer.[2] -
CORRECT ANSWER 1. to deflect
2. to accelerate
why is the first ionisation energy of krypton greater than that of bromine?[2] -CORRECT
ANSWER Krypton has more protons than bromine
but its outer electrons are in the same shell.
why is the first ionisation energy of aluminium less than the first ionisation energy of
magnesium.[2] -CORRECT ANSWER Al outer electron in 3p orbital and Mg outer
electron in 3s
energy of 3p is greater than 3s
State how the relative molecular mass of a covalent compound is obtained from its
mass spectrum.[1] -CORRECT ANSWER Mr = highest m/z value 1
State the block in the Periodic Table in which sulphur is placed and explain your
CORRECT ANSWER.[2] -CORRECT ANSWER p
outer orbital is 3p
State the relative charge and relative mass of a proton, of a neutron and of an electron.
In terms of particles, explain the relationship between two isotopes of the same
element.
Explain why these isotopes have identical chemical properties.[7] -CORRECT
ANSWER proton:mass 1 charge +1
neutron:mass 1 charge 0
electron: mass 1/1840 charge -1
isotopes have the same number of protons but a different number of neutrons.
isotopes have the same electronic configuration
chemical properties depend on electrons
Define the term relative atomic mass. An element exists as a mixture of three isotopes.
Explain, in detail, how the relative atomic mass of this element can be calculated from
data obtained from the mass spectrum of the element. [7] -CORRECT ANSWER -
weighted average mass of an element compared to 1/12 of an atom of carbon 12.
-spectrum gives relative abundance
