226. If in a 2-liter flask with a movable piston, at a certain temperature, $\text{PCl}_5$ grams are given, then after formation of 71 grams of chlorine gas, the equilibrium: $\text{PCl}_5(\text{g}) \rightleftharpoons \text{PCl}_3(\text{g}) + \text{Cl}_2(\text{g})$, $K = 1\ \text{mol.L}^{-1}$ is established. Under these conditions and at constant volume, if the reaction goes to half, the reaction shifts in which direction and the initial amount of $\text{PCl}_5$ was how many moles? $(\text{Cl} = 35/5\ \text{g.mol}^{-1})$ (1) forward, 2.5 (2) forward, 1.5 (3) backward, 2.5 (4) backward, 1.5
\textbf{226.} If in a 2-liter flask with a movable piston, at a certain temperature, $\text{PCl}_5$ grams are given, then after formation of 71 grams of chlorine gas, the equilibrium: $\text{PCl}_5(\text{g}) \rightleftharpoons \text{PCl}_3(\text{g}) + \text{Cl}_2(\text{g})$, $K = 1\ \text{mol.L}^{-1}$ is established. Under these conditions and at constant volume, if the reaction goes to half, the reaction shifts in which direction and the initial amount of $\text{PCl}_5$ was how many moles?
$(\text{Cl} = 35/5\ \text{g.mol}^{-1})$
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(1) forward, 2.5 \quad (2) forward, 1.5 \quad (3) backward, 2.5 \quad (4) backward, 1.5
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