Which one of the following elements shows variable valency?
Which of the following elements does not show variable valency?
Write the name of two elements, which show variable valency.
Which of the following shows variable valencies ?
What is variable valency ? Give two examples of elements showing variable valency.
Among the following identify the elements which show a variable valency?
Cu, Zn, Co, Fe, Sn, Pb, Ba, and Al.