As we draw electric current from the Daniel cell, the concentration of Zn2+ gradually___________ and the concentration of Cu2+ gradually___________

increases, decreases Zn(s)→Zn (aq)2++2e−1; Cu (aq)2++2e−1→Cu(s);  The half-cell reactions responsible for generation of electric current are as follows: As more Zn2+ ions are produced, its concentration increases. As Cu2+ions are consumed, its concentration decreases.