] For a fixed amount of gas at a fixed temperature, M and T is constant. ∴P∝d So graph between pressure (P) and density (d) is a straight line. Also,
P
d
=
RT
M
⇒
P
d
∝T [as R,M= constant ] ∴ When temperature T increases then slope of graph between P and d increases. As T3>T2>T1 then slope of T3 will be highest then T2 and then T1. So, graph (B) is the right graph.