According to ideal gas law, PV=nRT
P(atm) = 740/760 = 0.9737atm
T(K) = 25+273 = 298K
V = 0.3L
R = 0.082 atm*L/mol*K (constant)
n = PV/RT = 0.9737*0.3/(0.082*298) = 0.012mol
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T2 = -15+273 = 258 K
P2 = 805/760 = 1.06atm
PV=nRT
V=nRT/P = 0.012*0.082*258/1.06 = 0.24L
