Question

define mendeleev's periodic table? what are the achievement of Mendeleev? write it's demerits​

Answer 1

Answer:

The properties of this element are periodic functions of their atomic mass

Answer 2

$\sf\underline{Mendeleev's~Periodic~law :}$

The properties of the elements are the periodic functions of their atomic weights.

• His periodic table had 8 groups and 7 periods

$\sf\underline{Achievements :}$

• Division of elements into groups and periods (systematic division)
• Correction of few atomic weights
• Predicting the properties of missing elements like scandium and gallium

$\sf\underline{Limitations:}$

• Anomalous pairs of elements - Mendeleev placed elements with higher atomic weights before lower ones, Ex : Te and I
• Dissimilar elements placed together - Elements with dissimilar properties were placed in same groups like IA and IIA have small resemblance

Have a good night!