1. Atomic Structure and Periodic Table
1. An element X in the periodic table is represented as:
𝑍𝐴𝑋
a) What is denoted by ‘A’ and ‘Z’?
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b) Negative ion of X, X- has same number of electrons as argon
i) What is the name of element X?
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ii) Give electronic configuration of one atom of element X
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[Total 3 marks]
2. Mass spectrum can be used to calculate relative atomic mass of elements. Mass spectrum of
zirconium (Zr) is shown below:
a) Calculate relative atomic mass of zirconium.
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[2]
b) Element Copper (Cu) has a relative atomic mass of 63.5. Two isotopes of copper exist: 63Cu and 65Cu.
Construct the mass spectrum of copper.
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[Total 4 marks]
3. Isotopes of many elements exist in nature.
a) Define the term isotope
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b) Explain with reason whether following statement is true or not.
‘Isotopes have similar chemical properties but may have different physical properties’
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[Total 3 marks]
4. Successive ionization energies of an element X are given below:
a) When X is ionized, what must be the charge on stable ion of X? Explain how you arrived at your
answer.
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b) Draw two possible shapes of orbitals present in valence shell of this element
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[Total 4 marks]
5. Mass spectrum of a molecule is shown below
a) Define Relative molecular mass.
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b) What is the Mr of this molecule?
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[Total 2 marks]
6. Successive ionization energies of an element are plotted in the graph shown below
a) Define First Ionization Energy.
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b) Assuming the element has total 6 electrons
i) Draw orbital spin diagram of this element
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ii) Explain the large jump between 4th and 5th ionization energy.
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[3]
[Total 6 marks]
7. The variation in first ionization energy of 3rd period of elements are shown below:
a) List the elements of period three that belong to
i) s-block __________________________________________________________________________ ii)dblock ____________________________________________________________________
iii) p-block ___________________________________________________________________
[3]
b) Suggest why Al has a lower first ionization energy than Magnesium?
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[Total 6 marks]
8. Following elements are part of period 3 of periodic table.
Mg, Si, P, Cl
a) List these in order of increasing melting and boiling points.
Lowest
Highest
[2]
b) Explain in terms of structure and bonding your choice of element as having highest melting and boiling
point.
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[4]
[total 6 marks]
9. Atomic radius of elements changes across a period.
a) state the general trend of atomic radius in period 3 as we move from left to right?
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b) Explain the reason behind your answer to (a).
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[Total 4 marks]
10. This question is about electronic configuration.
a) State with reason whether the following statement is true or false?
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‘Atomic emission spectra provide evidence for the existence of quantum shells’
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b) Magnesium metal belongs to group 2 of periodic table.
Give electronic configuration of magnesium ion.
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11. Phosphorous and sulphur both belong to period three of periodic table.
a) State which of these has higher first ionization energy than the other?
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b) Explain the reasoning behind your answer to (a).
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[Total 3 marks]
12. The graph below shoes the variation of first ionization energies of elements across periods.
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a) In period 4, from K to Zn, ionization energies are very close together.
i) Suggest the block of periodic table these elements belong to
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ii) Suggest why the ionization energies are close together?
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b) what is the general trend of first ionization energies down a group?
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c) Describe the general trend of ionization energies along a period. Suggest the reason behind the trend.
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[4]
[Total 7 marks]
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13. First ionization energy of magnesium is greater than that of sodium but second ionization energy of
magnesium is lower than that of sodium
a) Define Second Ionization Energy.
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b) Write equation of second ionization of magnesium
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c) Explain why second ionization energy of magnesium is lower than that of sodium
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[Total 4 marks]
14. Explain how the following factors affect the ionization energy of atoms.
a) Attraction of nucleus
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b) distance of electron from nucleus
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c) shielding effect
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[Total 3 marks]
15. Bromine has two isotopes Br79 (50%) and Br81(50%).
a) Why are chemical properties of both isotopes the same?
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b) The mass spectrum of bromine gives 3 peaks. Draw possible mass spectrum of bromine.
[2]
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[Total 3 marks]
16. The table below gives information about sub-atomic particles
a)Complete the table
[3]
b) Define Atomic number
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c) Define Mass number
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[Total 4 marks]
17. Phosphorous, sulphur and chlorine belong to same period of the periodic table.
a) list them in order of increasing first ionization energy.
Lowest
Highest
[2]
b) Explain your answer to (a)
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[Total 5 marks]
18. Electronic configuration of an element is given below:
1s22s22p63s23p2
a) Identify the element.
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b) Draw the orbital spin diagram of neutral atom of this element .
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[1]
[Total 2 marks]
19. Electronic configuration of an element is given below
1s22s22p63s23p64s2
a) Identify the element from the periodic table
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b) Give electronic configuration of its ion
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c) Draw shapes of p and s orbital
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[Total 4 marks]
20. Period 3 of periodic table does not contain transition metals.
a) State which block of periodic table do the transition metals belong to?
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b) State p block elements of period 3.
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c) List the elements you answered in (b) in order of decreasing atomic radii.
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