Chemistry - PERIODIC TABLE Question with Solution | TestHub
Statement I :- Ba have highest atomic radius among s-block elements excluding radioactive elements. Statement II :- Down the group atomic size generally increases.
Options:
Answer:
Solution:
Statement I is false: Across any period from left to right, atomic radius decreases due to an increase in effective nuclear charge. Since Cesium (Cs) is to the left of Barium (Ba) in Period 6, Cs has a larger radius than Ba, making Cs the largest non-radioactive s-block element.
Statement II is true: As you move down any vertical group in the periodic table, the principal quantum number increases because new principal electronic shells are continuously added to the atoms.
Size Trend: The addition of these inner shells successfully shields the outermost electrons from the nucleus, overcoming the increase in nuclear charge and causing the atomic size to generally increase down the group.
