Final answer:
To fully hydrogenate 1.68 g of adiponitrile, 1.88 liters of H2 gas at STP are required.
Step-by-step explanation:
To find the volume of hydrogen gas (H2) required to fully hydrogenate 1.68 g of adiponitrile (C6H8N2), we need to use stoichiometry and the ideal gas law. In the given reaction, it is mentioned that 1 mole of adiponitrile requires 4 moles of hydrogen gas, so we can use this ratio to calculate the moles of hydrogen gas required.
First, we calculate the moles of adiponitrile:
1.68 g C6H8N2 × (1 mol C6H8N2 / 80.14 g C6H8N2) = 0.02098 mol C6H8N2
Using the stoichiometry, we find the moles of hydrogen gas:
0.02098 mol C6H8N2 × (4 mol H2 / 1 mol C6H8N2) = 0.08392 mol H2
Now we can use the ideal gas law to find the volume of hydrogen gas at STP (Standard Temperature and Pressure):
0.08392 mol H2 × (22.4 L / 1 mol H2) = 1.88 L
Therefore, 1.88 liters of H2 gas at STP are required to fully hydrogenate 1.68 g of adiponitrile.