Question

Justify presence of 18 elements in 5th group give answer on the basis of class 11.... no wrong answers

Answer 1

while filling 5th shell according to aufbau principle 5s , 5p , 4d filled so 2 +6+10 = 18 electrons or elements are present in 5th shell .

we start the 5th period with 4s orbital . we can add 2 electrons in 4s . then we fill 6 electrons in 4p orbital . further we start filling the 4d orbital which can take 10 electrons . so in the 4th principal quantum energy stater, we can fill 18 electrons . thus 5th period has 18 electrons.....


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