In the following diagram for the first three periods of the periodic table, five elements have been represented by the letters a, b, c, d and e (which are not their chemical symbols)
(i) Select the letter which represents a halogen.
(ii) Select the letter which represents a noble gas.
(iii) What type of bond is formed between a and b?
(iv) What type of bond is formed between c and b?
(v) Which element form a divalent anion?
Give reasons for your choices.
Answers
The last group is of Noble Gases or Stable Elements
Explanation:
(i) the letter d which represents an alkali metal
(ii) the letter c which represents a noble gas
(iii) the letter e which represents a halogen
(iv) The bond formed between a and e is a covalent bond.
(v) The bond formed between d and e is an ionic bond.
Let us predict : properties of elements
Explanation:
1. The letters that represent halogen is : "b"
Because it is in group 17 with 7 valence electrons
2.The element that is noble gas is "e"
Because it is in group 18 with 8 valence electrons
3.The bond formed between a and b is covalent as a belongs to group 14 with valency +-4 and b belongs to group 17 with valency -1.Both are non metals .
4.The bond formed between c and b is ionic as c belongs to group 2 with valency +2 and b belongs to group 17 with valency -1.That is metal and non metal . so, ionic bond is formed .
5."d" will form divalent anion as it belongs to group 16 with 6 valence and electrons and valency -2 .
