Amongst the following hydroxides,the one which has the highest value of $K_{sp}$ at ordinary temperature is

State whether the following statements are True or False:
$(1)$ Plaster of Paris is used to join fractured bones and keep them immobilized.
$(2)$ Calcium carbonate and soil are the raw materials for cement production.

What is the effect of adding gypsum to cement?

Bleaching powder is obtained by the reaction of chlorine gas with ........

Addition of an oxalate solution to an aqueous solution containing a mixture of $Ba^{2+}$,$Sr^{2+}$,and $Ca^{2+}$ ions will precipitate:

Assertion : Both $Be$ and $Al$ can form complexes such as $BeF_4^{2-}$ and $AlF_6^{3-}$ respectively,$BeF_6^{3-}$ is not formed.
Reason : In case of $Be$,no vacant $d-$ orbitals are present in its outermost shell.