How many of the following oxides are amphoteric?
$BeO, ZnO, Sb_2O_3, CO, CaO, SO_2, SO_3$

Which of the following elements shows a high tendency to form peroxide?

Fill in the blanks:
$(1)$ Calcium and beryllium have flame colors of ...... and ....... respectively.
$(2)$ Quantitative analysis of calcium is carried out by ........
$(3)$ Beryllium powder on combustion burns brightly in air and gives ...... and .......
$(4)$ Beryllium hydroxide on dissolving in alkali gives .......

The thermal stability of $BaCO_3$,$CaCO_3$,$SrCO_3$,and $MgCO_3$ decreases in the order:

As the alkaline earth metals (except $Be$) tend to lose their valence electrons readily,they act as:

Heating compound $(A)$ produces a colorless gas and a residue $(B)$ which dissolves in water. Passing excess $CO_2$ gas through the aqueous solution of $(B)$ yields compound $(C)$,which is obtained in solid state. Gently heating compound $(C)$ gives back the white solid $(A)$. What is compound $(A)$?