Answer is: <span>because dissolved compounds can crystallizing from solution during filtration and forming crystals on the filter paper or funnel.
</span>Recrystallization<span> is a technique used to purify chemicals by dissolving both impurities and a compound in an appropriate solvent, either compound or impurities can be removed from the solution, leaving the other behind.</span>
This is a single replacement reaction. So the final products are a metal and a salt with replaced cation. In this case, the final products are copper (metal) and iron sulfate (salt).
<span>The reaction is N2 + 3H2 -> 2NH3
So the amount of NH3 formed is 2/3 of the amount of H2 = 2/3 * 13.7 = 9.13 Liters.</span><span>The answer is 9.13
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