Match the atoms which might substitute for one another. Match the items in the left column to the items in the right column.
If you want to answer this question, all you have to do is take a look at the periodic table. An element might substitute for another element if it is from the same family/column on the periodic table.
So, these are the atoms which might substitute for one another:
1. Si = C.C
2. K = A. Na
3. Nb = B. V
4. Cu = D. Ag
5. P = F. As
6. Mg = E. Ca
1. Si = C.C
2. K = A. Na
3. Nb = B. V
4. Cu = D. Ag
5. P = F. As
6. Mg = E. Ca
Explanation: