(a) Give the H-C-O bond angle in methyl formate H-C-O bond angle methyl formate (b) One dihedral angle in methyl formate relates the plane containing the O-C- O bonds to the plane y two structures of methyl formate: one in which this dihedral angle containing the Co-onds, identand the other in which it is 180 0° dihedral angle 80" dihedral angle.

Explanation:

The bond angle is said to be the angle between two atoms near or around the same atom for a given covalent compound. However, a dihedral angle is known as the angle formed between two planes. Bond angles are usually planar while dihedral angles are interplanar.  

The diagram below shows the structure of each compound.

c is the answer because when something is left after something evaporates that shows the chemical change.