Which of the following compounds release oxygen upon heating?

The disease known as fluorosis is caused by the reaction of excess fluorine in the body with which of the following?

$Al$ vessels should not be cleaned with materials containing washing soda because .............

$X$ and $Y$ are two metals. When burnt in air,$X$ forms only oxide while $Y$ forms oxide and nitride. The metals $X$ and $Y$ may be

Which of the following statements is correct for a highly pure dilute solution of sodium in liquid ammonia?

$A$ compound $(M_2O_2)$ of group $I$ element $(M)$ hydrolyses to form $M^{+}$,$OH^{-}$ and $X$. Another compound $(M'O_2)$ of group $I$ element $(M')$ hydrolyses to form $(M')^{+}$,$OH^{-}$,$X$ and $Y$. What are $X$ and $Y$ respectively?