Question

1. Which of the following statement(s) is/are correct?
A) Mendeleev's periodic law was based on atomic numbers of the element.
B) Zero group was not present in the periodic table when Mendeleev presented it.
C) The effective nuclear charge (Zn) is the atomic number minus shielding effect.
D) There are four transition series in the periodic table each one consists of 10 elements.
a) A, B, C
b) A, B, D
c) B, C, D
d) A, B, C, D​

Answer 1

Answer:

(ᴄ) ʙ, ᴄ, ᴅ

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