question_answer 46)

  Elements with valency 1 are (a) always metals                                                             (b) always metalloids                     (c) either metals or non-metals                                 (d) always non-metals

Answer:

  (c) Metals and non-metals both can have valency 1. Metals which have 1 valence electron and non-metals which have 7 valence electrons, have valency 1. It is because, metals loose their 1 and non-metals gain 1  to complete their octet.