Periodicity Review. Metals, non-metals & metalloids:. Periodicity Review. Physical Properties Atomic Radius. Periodicity Review. Physical Properties Ionic Radius. Periodicity Review. Physical Properties
98 649 660 1410 44 119 –101 –189
Na Mg Al Si P4 S8 Cl2 Ar
2Na + 2H2O 2NaOH + H2
2Na + Cl2 2NaCl
fluorine is a pale yellow gas;
chlorine is a yellow-green gas;
bromine is a reddish brown liquid;
iodine is a shiny black solid that sublimes
Cl2(aq) + 2Br–(aq) 2Cl–(aq) + Br2(aq)
Cl2(aq) + 2I–(aq) 2Cl–(aq) + I2(aq)
Cl2(aq) + 2F–(aq) NR
(Na+(aq) + OH–(aq))
(Mg+2(aq) + 2OH–(aq))
sodium < magnesium < aluminum < silicon
732 kJ mol–1 1442 kJ mol–1 7683 kJ mol–1 10559 kJ mol–1
(a) Account for the fact that the IE value for each electron
is larger than the previous one.
(b) Describe how these values can be used to determine the
electron configuration of the element involved.
(c) To what periodic family does this element belong?
(d) Account for the fact that the ionisation energies of the
noble gases are higher than those of the elements
immediately before and immediately after them on the
(a) Write an equation for the reaction between
sodium and water and state whether the
resulting solution is acidic, neutral or alkaline.
(b) Write an equation for the reaction between
chlorine and water and state whether the
resulting solution is acidic, neutral or alkaline. (c) Li, Na and K react with water. Which of the
three reactions will be the most vigorous?
Explain this at an atomic level.
(1) The early periodic tables were developed by correlating the physical and chemical properties of the elements with their respective atomic masses.
(a) List one chemical and one physical property which leads to the grouping together of
Lithium, sodium and potassium
Chlorine, bromine and iodine
Helium, neon and argon 
(b) What feature of atomic structure underlies the modern basis of the periodic table? 
(2)(a) How does the physical state of the halogens vary from fluorine to iodine? Explain any variations noted. 
(b) Discuss the reactions of the halogens (Cl2, Br2, I2) with halide ions (Cl–, Br–, I–). Include ionic equations as appropriate. Describe and account for any colour changes that take place. 
ELEMENT 1st I.E. 2nd I.E. 3rd I.E.
1 1060 1900 2920
2 1000 2260 3390
3 1260 2300 3850
4 1520 2660 3950
5 418 3070 4600
6 590 1150 4940
(3)The table to the right lists the first, second, and third ionisation energies (in kJmol–1) of six successive elements in the periodic table.
(a) Define the term ionisation energy of an element. 
(b) For an element M write equations to represent 1st, 2nd, and 3rd ionisation energies. 
(c) Which of the elements in the table is most likely to be an alkaline earth metal? Explain your answer. 
(d) Which element is most likely to be an inert gas? Explain your answer. 
(e) Suggest the names of a set of elements that could possibly represent the elements 1 to V1. 
(6) (a) State how the first ionisation energy varies down group 1.
(b) Li, Na, and K react with water. Which of the three reactions will be the most vigorous? Explain this at an atomic level.
(c) State whether the second ionisation energy of sodium is less than, the same as, or greater than the first ionisation energy. Explain your answer.
Symbol of element Na Mg Al Si P S Cl
Atomic radius / 10-12 m 186 160 143 117 110 104 99
Ionic radius / 10-12 m 98 65 45 42 212 190 181
(7) The values of atomic radius and ionic radius for the period 3 elements are given below.
(a) Explain why the atomic radius decreases from sodium to chlorine.
(b) The ionic radius of aluminium is smaller than its atomic radius. The ionic radius of phosphorus is greater than its atomic radius. Explain the large difference in ionic radius between aluminium and phosphorus. 
(8) (a) State the meaning of the term electronegativity. 
(b) State and explain the trend in electronegativity across period 3 from Na to Cl. 
(c) Explain why Cl2 rather than Br2 would react more vigorously with a solution of I–. 
(11) Table 9 of the Data Booklet gives the atomic and ionic radii of elements. State & explain
(a) the difference between the atomic radius of nitrogen and oxygen. 
(b) the atomic radius of nitrogen and phosphorus. 
(c) the atomic and ionic radius of nitrogen.