3 Are these compounds chiral or achiral? Draw diagrams to justify your answer. Hint redraw these molecules in a way that allows you to see if a plane of symmetry is present.

(a)(2R,3S)-2,3-dibromohexane, star (*) each chiral center.

Compounds with several chiral centres may have configurations referred to as meso. Meso configurations arise when the molecule can adopt a configuration with an internal mirror plane. When this occurs, the mirror image of a molecule with an internal mirror plane is an identical configuration. Thus, even though the molecule may possess several chiral centres, they are reflection of each other (within the molecule) thus resulting in an achiral meso form. This occurs for example for tartaric acid (Figure 3.1). Because of this, tartaric acid only has three stereoisomers instead of four. It has the two chiral (R,R) and (S,S) enantiomers, and the meso form. Figure 3.1. Stereoisomers of tartaric acid. Given the information above on meso forms, how many different stereoisomers do compounds A to D (Figure 3.2) have? Figure 3.2. Structure of compounds A, B, C and D.

3. The structure of (L)-menthol is shown below. How many chiral centers does this molecule possess? Starting from the top of the molecule, and moving in a clockwise direction, identify the absolute configuration (R or S) of each of these chiral centers.

Suppose compounds A and B are enantiomers.  What can be said about A and B (select all that apply). a. They are mirror images of eachother b. Neither contains a chiral center c. They consist of the same number & types of atoms d. They are superimposible e. They are NOT superimposable f. They are stereoisomers

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3. Determine whether the following statements are true or false. Completely fill in the circle in front of your chosen answer. (a) A compound with a plane of symmetry must be achiral. (b) A compound with two or more stereocenters must be chiral. (a) O True O False True O False

1. How many chiral centers are there in the following molecule? Identify them with an asterisk. a) لم بشه Br b)

Which molecule would be more polar, CH3F or CH3Cl? And why?

For some questions you will need to use the special periodic table attached in the below images! Treat Je, Qu, Ap, and Bg as NONMETALS! Identify each of the following structures as chiral or achiral AND circle the chiral carbon atoms in each structure that is chiral. (Look at attached images) Please Show your work so I can understand going forward.