MCQ
Which of the following processes takes place with decrease of entropy?
- ASolid $\to $ gas
- Bsugar $+$ water $\to $ solution
- ✓$NH_{3(g)} + HCl_{(g)} \to NH_4Cl_{(s)}$
- D$A_{(g)} + B_{(g)} \to $ mixture
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$^{200}X \,:\, 90\%$ $^{199}X\, :\, 8.0\%$ $^{202}X\, :\, 2.0\%$
The weighted average atomic mass of the naturally occurring element $X$ is closest to......$amu$
$CH _3\left( CH _2\right)_4 CH _3 \xrightarrow[HCl,\Delta]{Anhy.AlCl_3} X$

$A.$ $SO _{4}^{2-}$ and $CrO _{4}^{2-}$
$B.$ $SiCl _{4}$ and $TiCl _{4}$
$C.$ $NH _{3}$ and $NO _{3}^{-}$
$D.$ $BCl _{3}$ and $BrCl _{3}$
$BCl _{3}$ and $BrCl _{3}$