The diagrams below represent
ball-and-stick models of two molecules. In a ball-and-stick
model, each ball represents an atom, and the sticks between
balls represent chemical bonds.
59 Draw a Lewis electron-dot diagram for an
atom of the element present in all organic compounds. 
link to see answer to 59
60 Explain, in terms of carbon-carbon bonds,
why the hydrocarbon represented in diagram B is saturated.
|Answer==>All single bonds
61 Explain why the molecules in diagrams A and B are isomers
of each other. 
formula, but have different structural formulas