def NH3(mw_atmos, mh=1):
    """Defines properties for  NH3 as condensible"""
    if mh != 1:
        raise Exception(
            'Alert: No M/H Dependence in NH3 Routine. Consult your local theorist to determine next steps.'
            )
    gas_mw = 17.0
    gas_mmr = 0.000134 * (gas_mw / mw_atmos) * 1.0
    rho_p = 0.84
    return gas_mw, gas_mmr, rho_p
