An element with Z = 38 of modern periodic table belongs to same group as that of the element with Z =
Hints to predict the position of element in the Modern periodic table :
1)Elements from Z = 58-71……Lanthanoids…..4f series….6th period……3rd(IIIB) group;
2)Elements from Z = 90-103……Actinoids…..5f series….7th period……3rd(IIIB) group;
3)Elements from Z = 104-118………..Last two digits gives group number….. 7th period;
4)Elements from Z = 31-57….subtract 18 to get preceding element;
5)Elements from Z = 72-89….subtract 32 to get preceding element;
6)Elements from Z = 104-120….subtract 32 to get preceding element ;
For Z=104-120….simplest Hint
7)Elements from Z = 104-120….subtract 82 to get a lower member(Z<30) belonging to same group;
Hints 4, 5 and 6 can be used repeatedly until an element belonging to same group with Z < 30 is obtained;
Elements with Z < 30 with their group, period and block can be known from Electronic configuration;
Ex : Z=120, 88, 56, 38, 20, 12….belong to 2nd(IIA) group;
(120-32)=88; (88-32)=56; (56-18)=38; (38-18)=20;(20-8)=12;
Z = 12…..Mg….3s2…..n=3….3rd period……s-block….valence electrons(2)….2nd group;
Z = 20…..Ca….4s2…..n=4….4th period……s-block….valence electrons(2)…..2nd group;
Z = 38…..Sr….5s2…..n=5….5th period…….s-block….valence electrons(2)…..2nd group;
Z = 56…..Ba….6s2….n=6….6th period……..s-block….valence electrons(2)….2nd group;
Z = 88…..Ra….7s2….n=7….7th period……..s-block….valence electrons(2)…..2nd group;
Z = 120…Ubn..8s2….n=8…..8th period…….s-block….valence electrons(2)….2nd group;