$X + C + Cl_2 \xrightarrow[> 1000 \ K]{\text{High temp.}} Y + CO$
$Y + 2H_2O \to Z + 2HCl$
Compound $Y$ is found in a polymeric chain structure and is an electron-deficient molecule. $Y$ must be:

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

Which one of the alkaline earth metal carbonates is thermally the most stable?
$MgCO_{3}, CaCO_{3}, SrCO_{3}, BaCO_{3}$

The property of the alkaline earth metals that increases with their atomic number is

Given below are two statements:
Statement $I$: Both $CaCl_2 \cdot 6H_2O$ and $MgCl_2 \cdot 8H_2O$ undergo dehydration on heating.
Statement $II$: $BeO$ is amphoteric whereas the oxides of other elements in the same group are acidic.
In the light of the above statements,choose the correct answer from the options given below:

An element $P$ has atomic number $56$. What will be the formula of its halide?