# Problem: Assuming that the van der Waals equation predictions are accurate, account for why the pressure of H2 is higher than that predicted for an ideal gas.A) The pressure is higher than the ideal gas because there are strong intermolecular forces and the atoms are large. B) The pressure is higher than the ideal gas because there are weak intermolecular forces and the atoms are small. C) The pressure is higher than the ideal gas because there are strong intermolecular forces and the atoms are small. D) The pressure is higher than the ideal gas because there are weak intermolecular forces and the atoms are large.

###### FREE Expert Solution

Van der Waals equation takes into account attractive forces in a (polarity coefficient) and size in b (size coefficient):

$\overline{){\mathbf{P}}{\mathbf{=}}\frac{\mathbf{nRT}}{\left(\mathbf{V}\mathbf{-}\mathbf{nb}\right)}{\mathbf{-}}{\mathbf{a}}\frac{{\mathbf{n}}^{\mathbf{2}}}{{\mathbf{V}}^{\mathbf{2}}}}$

The values of a and b are relatively low for H2

• a = 0.244 L2 atm/mol2lower value → higher pressure
• b = 0.0266 L/mol (small)

While the ideal gas equation does not:

$\mathbf{P}\mathbf{=}\frac{\mathbf{nRT}}{\mathbf{V}}$

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###### Problem Details

Assuming that the van der Waals equation predictions are accurate, account for why the pressure of H2 is higher than that predicted for an ideal gas.

A) The pressure is higher than the ideal gas because there are strong intermolecular forces and the atoms are large.

B) The pressure is higher than the ideal gas because there are weak intermolecular forces and the atoms are small.

C) The pressure is higher than the ideal gas because there are strong intermolecular forces and the atoms are small.

D) The pressure is higher than the ideal gas because there are weak intermolecular forces and the atoms are large.