Which of the following holds good for a solution obeying Raoult's law (i.e., an ideal solution) (where, ΔH = heat of mixing, and ΔV = volume change on mixing )?

• ΔH = 1 (+ ve)and Δ V = -ve
• ΔH = 0
• ΔV = 0
• both (b) and (c)