Consider three metal chlorides $x, y$ and $z$, where $x$ is water soluble at room temperature, $y$ is sparingly soluble in water at room temperature and $z$ is soluble in hot water. $x, y$ and $z$ are respectively

Question

Accepted Answer

B. 1. **Why solubility behaviour is the key clue**: metal chlorides differ in solubility, so each description ($x$, $y$, $z$) must be matched to a chloride known for that exact behaviour.

2. **For $x$ (soluble at room temperature)**: common chlorides like $MgCl_2$, $AlCl_3$, and $CuCl_2$ dissolve readily in cold water, so $x$ should be one of these — here, $CuCl_2$ fits the option set.

3. **For $y$ (only sparingly soluble at room temperature)**: $AgCl$ and $Hg_2Cl_2$ are the classic examples of chlorides that barely dissolve in cold water, so $y = AgCl$.

4. **For $z$ (insoluble cold, soluble hot)**: $PbCl_2$ is the standard example that dissolves poorly in cold water but dissolves noticeably better in hot water — this is exactly why it's used to separate $Pb^{2+}$ from $Ag^+$ and $Hg_2^{2+}$ in group I analysis.

5. **Therefore**, matching all three: $x = CuCl_2$, $y = AgCl$, $z = PbCl_2$.

Hence, the answer is **B ($CuCl_2, AgCl$ and $PbCl_2$)**.

Consider three metal chlorides x,yx, yx,y and zzz, where xxx is water soluble at room temperature, yyy is sparingly soluble in water at room temperature and zzz is soluble in hot water. x,yx, yx,y and zzz are respectively

Consider three metal chlorides $x, y$ and $z$ , where $x$ is water soluble at room temperature, $y$ is sparingly soluble in water at room temperature and $z$ is soluble in hot water. $x, y$ and $z$ are respectively