def deltaT(tinit_mix, tboil_mix):
    """
    Calculates the difference temperatures between the initial and the ultimate temperatures of mix , [degrees celcium]
    Parameters
    ----------
    tinit_mix : float
        The initial temperature of mix, [degrees celcium]
    tboil_mix : float
        The boilling temperature of mix, [degrees celcium]
    Returns
    -------
    deltaT : float
        The difference temperatures between the initial and the ultimate temperatures of mix , [degrees celcium]
    References
    ----------
    Дытнерский, формула 2.2, стр.45
    """       
    return tinit_mix - tboil_mix