Identify the following compound from its IR and proton NMR spectra. C4H6O: NMR: δ 2.43 (1H, t, J = 2 Hz); δ 3.41 (3H, s); δ 4.10 (2H, d, J = 2 Hz) IR: 2125, 3300 cm–1 The C4H6O compound liberates a gas when treated with C2H5MgBr.

13. a covalent bond between two atoms is likely to be polar if: a. one of the atoms is much more electronegative than the other. b. the two atoms are equally electronegative. c. the two atoms are of the same element. d. the bond is part of a tetrahedrally shaped molecule. e. one atom is an anion.