| (1) $1/15$ | (2) $1/r\Delta$ | (3) $1/\Delta$ | (4) $1/V\Delta$ |
\textbf{205--} Metal A with halogen X forms the chemical compound $AX_r$. This compound reacts according to:
$$2AX_r(s) + X_r(g) \xrightarrow{\Delta} 2AX_r(s)$$
Upon decomposition, $1.12$ g of $AX_r$ is completely decomposed and $0.72$ g of $AX$ is formed and $71.25$ mL of halogen gas $X_r$ is produced. The atomic mass of X is equal to the atomic mass of metal A. (Take the molar volume of gases at experimental conditions to be $28.5$ liters.)
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(1) $1/15$ & (2) $1/r\Delta$ & (3) $1/\Delta$ & (4) $1/V\Delta$
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