Volumetric Properties of Binary Mixtures of 1-Butyl-1-Methylpyrrolidinium Tris(pentafluoroethyl)trifluorophosphate with N-Methylformamide, N-Ethylformamide, N,N-Dimethylformamide, N,N-Dibutylformamide, and N,N-Dimethylacetamide from (293.15 to 323.15) K

Experimental densities of binary mixtures of ionic liquid 1-butyl-1-methylpyrrolidinium tris(pentafluoroethyl)trifluorophosphate ([BMPYR] [FAP]) with two protic amides-N-methylformamide (NMF) and N-ethylformamide (NEF)-and three aprotic-N,N-dimethylformamide (DMF), N,N-dibutylformamide (DBF), and N,N-dimethylacetamide (DMA)-are reported in the temperature range from (293.15 to 323.15) K and at atmospheric pressure (0.1 MPa) over the whole composition range. This ionic liquid was selected due to its hydrophobic properties and hydrolytic stability. The excess molar volumes derived from the experimental densities appear to be positive for all of the studied mixtures in the whole composition range at all temperatures. The systems with aprotic amides (DMF, DBF, DMA) show higher values of excess molar volume compared to those with protic amides (NMF, NEF), while the number of the methyl groups at the carbon atom does not affect the composition corresponding to the maximum of the excess molar volume.