MCQ
In Mendeleev's periodic table, gaps were left for the elements to be discovered later. Which of the following elements found a place in the periodic table later?
- AGermanium
- BChlorine
- COxygen
- DSilicon
Explanation:
Chlorine, oxygen and silicon were included in Mendeleev's periodic table. Germanium was discovered later which fit into the empty spaces left by Mendeleev and matched to the expected properties.
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Volume, Molar heat capacity, Molarity, $E ^\theta$ cell, Gibbs free energy change, Molar mass, Mole
| Acid | $K_a$ |
| $HCN$ | $6.2\times 10^{-10}$ |
| $HF$ | $7.2\times 10^{-4}$ |
| $HNO_2$ | $4.0\times 10^{-4}$ |
Correct order of increasing base strength of the base $CN^-,F^-$ and $NO_2^-$ will be