Identify the most acidic oxide among the following oxides based on their reaction.

When $KI$ is passed through a solution containing $KCl, KF,$ and $KBr$,what happens?

The periodic trend of chemical reactivity for alkali metals and halogens is described in the following statements. Which statement provides the correct concept?

Choose the correct order of acidic strength for $CO_2, CuO, CaO, H_2O$.

Which of the following electronic configurations represents a coinage metal?

The electronic configurations of four elements are:
$I.$ $[Kr]\, 5s^1$
$II.$ $[Rn]\, 5f^{14}\, 6d^1\, 7s^2$
$III.$ $[Ar]\, 3d^{10}\, 4s^2\, 4p^5$
$IV.$ $[Ar]\, 3d^6\, 4s^2$
Consider the following statements:
$(i)$ $I$ shows variable oxidation state
$(ii)$ $II$ is a $d$-block element
$(iii)$ The compound formed between $I$ and $III$ is covalent
$(iv)$ $IV$ shows single oxidation state
Which statement is True $(T)$ or False $(F)$?