Question
State any three limitations of Mendeleev’s classification of elements.
✓
Answer
Limitations of Mendeleevs classification of elements:
- The position of isotopes could not be explained.
- Wrong order of atomic masses of some elements could not be explained.
- A correct position could not be assigned to Hydrogen in the periodic table.
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→$\begin{matrix}\text{B}&110\times10^{-8}\Omega\text{ m}\\\text{C}&2.60\times10^{-8}\Omega\text{ m}\\\text{D}&10.0\times10^{-8}\Omega\text{ m}\\\text{E}&1.70\times10^{-8}\Omega\text{ m}\end{matrix}$
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i. Calcareous spines are present on the body. Tube feet are used for locomotion and capturing prey also.
- Identify the phylum and give one example.
ii. I live in your small intestine. Pseudocoelom is present in my thread like body.
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