Question

which of the following groupings contains only representative elements?

al, mg, li

hg, cr, ag

cu, co, cd

ni, fe, zn

Explanation:

Representative elements are elements from the s - block (Groups 1 and 2) and p - block (Groups 13 - 18) of the periodic table.

• For \(Al,Mg,Li\):
• \(Li\) is in Group 1 (s - block).
• \(Mg\) is in Group 2 (s - block).
• \(Al\) is in Group 13 (p - block). All are representative elements.
• For \(Hg,Cr,Ag\):
• \(Hg\) is in Group 12 (d - block).
• \(Cr\) is in Group 6 (d - block).
• \(Ag\) is in Group 11 (d - block). These are transition (d - block) elements, not representative elements.
• For \(Cu,Co,Cd\):
• \(Cu\) is in Group 11 (d - block).
• \(Co\) is in Group 9 (d - block).
• \(Cd\) is in Group 12 (d - block). These are transition (d - block) elements, not representative elements.
• For \(Ni,Fe,Zn\):
• \(Ni\) is in Group 10 (d - block).
• \(Fe\) is in Group 8 (d - block).
• \(Zn\) is in Group 12 (d - block). These are transition (d - block) elements, not representative elements.

Answer:

\(Al,Mg,Li\)