Which of the following statement about the Mendeleev’s periodic table is correct ?
Answers
Answer:
Answer
Mendeleev's periodic table is based on increasing order of atomic weights.
It follows the periodic law which states that the physical and chemical properties of elements are a periodic function of their atomic weights.
Hence, the statement (i) is incorrect and (iv) is correct.
Mendeleev corrected the atomic weight of some elements like Be, In, Au, Pt etc based on their position in the periodic table.
For example, the atomic mass of beryllium was corrected from 13.5 to 9. Hence, the statement (ii) is correct.
The inverted pairs are (Ar,K), (Co,Ni) and (Te, I
2
). They are also called anomalous pairs. Their positions are not justified.
Hence, the statement (iii) is incorrect.
Explanation:
Medium
Answer
Mendeleev's periodic table is based on increasing order of atomic weights.
It follows the periodic law which states that the physical and chemical properties of elements are a periodic function of their atomic weights.
Hence, the statement (i) is incorrect and (iv) is correct.
Mendeleev corrected the atomic weight of some elements like Be, In, Au, Pt etc based on their position in the periodic table.
For example, the atomic mass of beryllium was corrected from 13.5 to 9. Hence, the statement (ii) is correct.
The inverted pairs are (Ar,K), (Co,Ni) and (Te, I
2
). They are also called anomalous pairs. Their positions are not justified.