def getHydrogens(soluteFile):
    """Get number of hydrogen atoms
    The # hydrogens is used in when applying Alberty's Legendre Transform.
    """
    with open(soluteFile, 'r') as f:
        lines = f.readlines()[2:]
        nH = len([line.split()[0] for line in lines if line.split()[0] == 'H'])
    return nH