Dimitiriy Ivanovich Mendeleyev (1834-1907)Rosiyaning Tobuliski shahrida shifikorlar oilasida tug’ilgan. Mendeleyev oilada 17-farzand bo’lib tug’ilgan. Davriy sistemada XX -asrda 60 ta element malum edi

Dimitiriy Ivanovich Mendeleyev (1834-1907)Rosiyaning Tobuliski shahrida shifikorlar oilasida tug’ilgan.Mendeleyev oilada 17-farzand bo’lib tug’ilgan .Davriy sistemada XX –asrda 60 ta element malum edi.xozirgi kunda 118-element mavjud bo’lib 96-tasi metal 22-tasi metalmas xisoblanadi .Davriy sistemada 4 oila bo’lib 1.S-oila 2.P-oila 3.d-oila 4.-f oila bulardan 14-s element 36-p element 40-d element 28-f element hisoblanadi.Davriy sistemada 8-gruppa 11-qator 7-davrdan iborat.Davriy sistemada eng qimmat metal Xozirgi kunda Cf-Kaliforniy xisoblanadi.Eng yengil metal Li-litiy eng qattiq metall Cr-xrom eng yumshoq metall Na-natriy eng og’ir metall Os-osmiy xisoblanadi.