Home › CBSE Class 11 (Science) › Chemistry › Classification of Elements › How many periods does the modern long form arran…
How many periods does the modern long form arrangement of elements have?
ASeven
BSix
CNine
DEight
Answer & Solution
Correct answer: A. Seven
There are seven periods, matching the highest principal quantum numbers n = 1 to 7.
Related questions
Down a group, why do metallic properties generally increase?What is nuclear charge defined as?How does nucleophilicity generally change from left to right across a period?From group 1 to the noble gases, how does valency change?Ionization energy is also referred to by which other name?In group 13, how does electronegativity change from boron to thallium?Down a transition group, ionization enthalpy shows what trend versus main groups?Carbon monoxide, nitric oxide and nitrous oxide are examples of which type of oxide?