According to lother mayer mandaleef concluded that physical and chemical properties of elements are periodic functions of their atomic weights but later mosleys experiment concluded that frequency directly proportional to atomic no so from that modern periodically table based on atomic no. this is primary difference
Eka aluminum is gallium, Eka silicon is germanium. their properties are aluminum exist as Al2o3 and gallium exist as Ga2o3, and also like silicon exists as sio2, germanium exists as Geo2, like carbon it exists as cH4, Geo4
Minerals are remobilised from older dying leaves to younger leaves. small amount of material exchange take place between xylem and phloem. hence minerals are not lost