Three elements from Group 1 and three elements from Group 17 are given in the table with their relative atomic masses.
Group 1 Group 17
lithium (7) fluorine (19)
sodium (23) chlorine (35.5)
potassium (39) bromine (80)
Of the elements in the table, one mole of the most reactive Group 1 element is reacted with one mole of the Group 17 element with the highest boiling point. What is the maximum mass of the salt formed by this reaction?

Answer:

22) D

Out of the Group 1 elements shown, potassium is the most reactive.
Out of the group 17 elements shown, bromine has the highest boiling point.
Potassium
Moles (n) = 1
Mr = 39
m = nx Mr 1x 39 =
Bromine
Moles (n) = 1
Mr = 80
39 g
m = nx Mr = 1x 80 = 80 g
Total mass = 39 +80= 119 g