Identify the compound formed from elements $X, Y, Z$ having oxidation states $+2, +5, -2$ respectively.

Mohr's salt is

$10 \ mL$ of $2 \ M$ $NaOH$ solution is added to $20 \ mL$ of $1 \ M$ $HCl$ solution kept in a beaker. Now,$10 \ mL$ of this mixture is poured into a volumetric flask of $100 \ mL$ containing $2 \ moles$ of $HCl$ and made the volume up to the mark with distilled water. The solution in this flask is $:$

What are the different elements present in the mineral barite?

Which chemical reaction contains incorrect products?

What is the importance of chemistry?