• Question: Carbon is above lead in group 4. I thought elements were more reactive as you go down a group in the periodic table, but carbon is above lead in the reactivity series. How come?

    Asked by Dr.Brian to Alex, Anaïs, Peter, Sarwat, Shreesha on 6 Mar 2015.
    • Photo: Sarwat Iqbal

      Sarwat Iqbal answered on 6 Mar 2015:

      Do you want to ask why is carbon very reactive?
      Carbon has four outer electrons and needs to gain four electrons to complete the shell set. Those electrons are rather close to the nucleus so that the bonds are energetic. Carbon takes/shares one two three or four electrons. A very active reactant!!

    • Photo: Alexander Henderson

      Alexander Henderson answered on 6 Mar 2015:

      As you go down group 1, the elements (alkali metals) do indeed get more reactive; however, the reverse trend can applied in group 7, with fluorine being most reactive. Carbon, in group 4, is sort of between the two extremes and readily forms 4 bonds; however, be-careful how you think about reactivity – diamond is very stable but coal can be burnt! Progressing down group 4 you go from non metals (e.g. C) to metalloids (Si and Ge) to metals (Sn and Pb). Non-metals (e.g. C) and metals (e.g. Pb) exhibit vastly different behaviour due to the type and number of bonds they would preferentially form.

Comments