Question

Identify the name of method used for three dimensional representation of molecule as follows.

• A. Wedge formula
• B. Fisher projection formula
• C. Newman projection formula
• D. Sawhorse formula

Hint:

Fischer = Flat cross; Wedge = Solid/Dashed triangles; Newman = Circle view.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
To visualize the 3D structure of molecules on a 2D surface, chemists use various standardized projection formulas.
Recognizing the visual characteristics of each method is key to identifying them.
Step 2: Key Formula or Approach:
Compare the visual features of the provided image with the definitions of the four main stereochemical projections:
- Wedge-dash: Uses solid and dashed wedges to show depth.
- Newman: Uses a circle to represent the front-to-back axis of a specific bond.
- Sawhorse: Shows the molecule at an angle, representing a specific bond as a slanted line.
- Fischer: Uses a simple 2D cross to represent a 3D chiral center.
Step 3: Detailed Explanation:
Let's analyze the given image:
The image displays a molecule (lactic acid) represented by two intersecting lines forming a cross.
At the intersection is an implied chiral carbon atom.
The four groups (\( \text{COOH} \), \( \text{H} \), \( \text{OH} \), \( \text{CH}_3 \)) are written at the ends of the cross.
This specific layout is the defining characteristic of a Fischer projection.
In a Fischer projection, there is a strict 3D convention implied by the 2D drawing:
- Horizontal lines represent bonds that are projecting forward, out of the page towards the viewer.
- Vertical lines represent bonds that are projecting backward, into the page away from the viewer.
None of the other options use this simple cross representation. Wedge formulas explicitly draw wedges; Newman projections use circles; Sawhorse projections draw an elongated slanted bond.
Step 4: Final Answer:
The representation shown is a Fisher projection formula.