Physi­co-Chem­i­cal Prop­er­ties of Ion­ic Liquids

Ion­ic liq­uids are salts in which ions are coor­di­nat­ed in a poor man­ner. This is why these sol­vents remain liq­uid below 100^○C, as well as at room tem­per­a­ture. Ion­ic liq­uids are con­sid­ered as green sol­vents and pos­sess many unique qual­i­ties. One impor­tant aspect that should be kept in mind about ion­ic liq­uids is that they can be dra­mat­i­cal­ly altered by impu­ri­ties such as organ­ic sol­vents, water and chlo­ride ions. To learn about a chem­i­cal, it is impor­tant that its phys­i­cal and chem­i­cal prop­er­ties are known. Here are few sig­nif­i­cant physi­­co-chem­i­­cal prop­er­ties of ion­ic liquids : 

Melt­ing Points

This is the most sig­nif­i­cant char­ac­ter­is­tic of ion­ic liq­uids ! Cations and anions are two types of ions that ion­ic liq­uids pos­sess. Selec­tion of these two aspects deter­mines the melt­ing point of an ion­ic liq­uid. A cation with a low sym­me­try will have a low melt­ing point, as com­pared to the one with a high sym­me­try. Poor inter­mol­e­c­u­lar inter­ac­tions with an appro­pri­ate dis­tri­b­u­tion of charge in the cation will result in a low melt­ing point.

Den­si­ties

Ion­ic liq­uids are denser than water. Cation and anion deter­mine the mag­ni­tude of den­si­ty. An increase in the bulk­i­ness of the organ­ic cation caus­es a decrease in the den­si­ty of ion­ic liq­uid. Addi­tion­al­ly, the den­si­ty of the ion­ic liq­uid depends on the choice of the anion.

Ther­mal Stability

Almost all the ion­ic liq­uids are sta­ble at and above 400^○C. Instead of cations, the nature of anions deter­mines the ther­mal decom­po­si­tion of ion­ic liq­uids. An increase in the hydrophilic­i­ty of anions caus­es a decrease in the ther­mal decom­po­si­tion. Report­ed­ly, var­i­ous ion­ic liq­uids have dif­fer­ent ther­mal sta­bil­i­ty, which is why it is sug­gest­ed that decom­po­si­tion of tem­per­a­ture of ion­ic liq­uids should be cal­cu­lat­ed via fast ther­mo­gravi­met­ric analy­sis (TGA) scans.

Dif­fu­sion and Conductivity

Learn­ing about con­duc­tiv­i­ty and dif­fu­sion helps in effec­tive appli­ca­tion of ion­ic liq­uids. How­ev­er, an appro­pri­ate and prop­er rela­tion­ship between the trans­port prop­er­ties and chem­i­cal struc­tures is not inves­ti­gat­ed yet. This is why two equa­tions, Nernst-Ein­stein and Stokes-Ein­stein are used to ana­lyze the ion­ic dif­fu­sion of ion­ic liq­uids. These equa­tions revealed that ion­ic size and ion pairs play a vital role in deter­min­ing the con­duc­tiv­i­ty of ion­ic liq­uids. With its unique advan­tages, a num­ber of com­pa­nies are uti­liz­ing ion­ic liq­uids in their busi­ness. Wat­son Inter­na­tion­al, being an FCAD com­pa­ny, is one of the finest chem­i­cal dis­trib­u­tors. We make sure that high qual­i­ty chem­i­cals are man­u­fac­tured and offered to our clients for their business.