MCQ
$X$ is


- A

- ✓

- C

- D







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Atomic mass of $\mathrm{K}=39, \mathrm{Mn}=55, \mathrm{O}=16]$
(Use molar mass of aluminium as $27.0 g mol ^{-1}, R =0.082 atm L mol { }^{-1} K ^{-1}$ )