Five moles of an ideal gas at 293 K is expanded isothermally from an initial pressure of 2.1 MPa to 1.3 MPa against at constant external pressure 4.3 MPa. The heat transferred in this process is _________ kJ mol^$-$1. (Rounded off to the nearest integer) [Use R = 8.314 J mol^$-$1K^$-$1]