Ethylammonium nitrate, CH₃CH₂NH₃NO₃, was the first ionic liquid to be discovered. Its melting point of 12 °C was reported in 1914, and it has since been used as a nonpolluting solvent for organic reactions and for facilitating the folding of proteins.

(a) Draw the Lewis structure of each ion in ethylammonium nitrate and indicate the formal charge on each atom (in the cation, the carbon atoms are attached to the N atom in a chain: C—C—N).

(b) Assign a hybridization scheme to each C and N atom.

(c) Ethylammonium nitrate cannot be used as a solvent for some reactions because it can oxidize some compounds.

Which ion is more likely to be the actual oxidizing agent, the cation or the anion? Explain your answer.

(d) Ethylammonium nitrate can be prepared by the reaction of gaseous ethylamine, CH₃CH₂NH₂, and aqueous nitric acid. Write the chemical equation for the reaction. What type of reaction is this?

(e) In an experiment, 2.00 L of ethylamine at 0.960 atm and 23.2°C was bubbled into 250.0 mL of 0.240 M HNO₃(aq), and 4.10 g of ethylammonium nitrate was produced. What were the theoretical and percentage yields of the salt?

(f) Suggest ways in which the forces that hold ethylammonium nitrate ions together in the solid state differ from those that hold together salts such as sodium chloride or sodium bromide.

(g) Low-melting salts in which the cation is inorganic and the anion organic have been prepared. Explain the trend in melting point seen in the following series: sodium acetate (NaCH₃CO₂), 324°C; sodium propanoate (NaCH₃CH₂CO₂), 285 8C; sodium butanoate (NaCH₃CH₂CH₂CO₂), 76 °C; and sodium pentanoate (NaCH₃CH₂CH₂CH₂CO₂), 64 °C.