It has 18 groups and 8 periods
It has 18 groups and 10 periods
It has 18 groups and 7 periods
It has 8 groups and 7 periods
Potassium,silicon,strontium,argon
Beryllium,barium,calcium,radium
Hydrogen,lithium,cesium,sodium
Zirconium,platinum,darmstadtium,nickel
Calcium
Xenon
Copper
Hydrogen
Group 2
Group 8
Group 14
Group 18
Na
Br
Fe
O
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