A line-angle (skeletal) representation is shown below using text symbols
CHEMISTRY · Multi-part · A Level · Chemistry · Introduction to organic chemistry · Introduction to organic chemistry
Problem
A line-angle (skeletal) representation is shown below using text symbols.
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The drawing consists of two connected straight-line segments that form a simple zig-zag with three vertices (two line segments). No additional symbols are attached to any vertex.
Assume normal conventions for skeletal structures: every vertex represents a carbon atom, hydrogens bonded to carbon are not shown, and lone pairs are omitted unless required.
Answer the following about this representation of a hydrocarbon.
(a) Identify the molecular formula of the hydrocarbon depicted, including the total number of carbon and hydrogen atoms. Show how you arrived at each count.
(b) Explain, in prose, how the implied hydrogens are determined for each carbon in a line-angle diagram of an unbranched alkane.
(c) Draw a complete Lewis electron-dot structure for the molecule, explicitly showing every atom, every bond, and all lone pairs (if any). Label all bond angles qualitatively (linear, bent, or tetrahedral) without measuring numerical values.
(d) Describe one advantage and one limitation of the line-angle representation compared with the full Lewis structure for the molecule you drew in part (c).