N2 - The nonlinearity parameter B/A, internal pressure, and acoustic impedance are calculated for a room temperature ionic liquid, i.e. for 1-ethyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide for temperatures from (288.15 to 318.15) K and pressures up to 100 MPa. The B/A calculations are made by means of a thermodynamic method. The decrease of B/A values with the increasing pressure is observed. At the same time B/A is temperature independent in the range studied. The results are compared with corresponding data for organic molecular liquids. The isotherms of internal pressure cross at pressure in the vicinity of 70 MPa, i.e. in this range the internal pressure is temperature independent. L1 - http://www.journals.pan.pl/Content/101327/PDF/aoa-2016-0006.pdf L2 - http://www.journals.pan.pl/Content/101327 PY - 2016 IS - No 1 EP - 66 DO - 10.1515/aoa-2016-0006 KW - nonlinearity parameter KW - speed of sound KW - high pressure KW - ionic liquids KW - internal pressure A1 - Zorębski, Edward A1 - Zorębski, Michał A1 - Dzida, Marzena PB - Polish Academy of Sciences, Institute of Fundamental Technological Research, Committee on Acoustics VL - vol. 41 DA - 2016 T1 - Acoustic Nonlinearity Parameter B/A, Internal Pressure,and Acoustic Impedance Determined at Pressures up to 100 MPafor 1-Ethyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide SP - 59 UR - http://www.journals.pan.pl/dlibra/publication/edition/101327 T2 - Archives of Acoustics