Noble metals,like gold and platinum,are soluble in which of the following mixtures?

$F_2$ is a stronger oxidizing agent than $Br_2$ due to..........

Which one of the following orders is not in accordance with the property stated against it?

An inorganic white crystalline compound $(A)$ has a rock salt structure. $(A)$ on reaction with conc. $H_2SO_4$ and $MnO_2$ evolves a pungent smelling,greenish-yellow gas $(B)$. Compound $(A)$ gives a white precipitate of $(C)$ with $AgNO_3$ solution. Compounds $(A)$,$(B)$,and $(C)$ will be respectively:

What is produced when bleaching powder reacts with dilute hydrochloric acid?

When treated with conc. $HCl$,$MnO_2$ yields a gas $(X)$ which further reacts with $Ca(OH)_2$ to generate a white solid $(Y)$. The solid $Y$ reacts with dil. $HCl$ to produce the same gas $X$. The solid $Y$ is