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	Let's now consider Sn where n is odd. For the BF3 molecule, for instance, we might think that S3 ≡ C3, but this only appears to be the case because the molecule is planar. In fact, S3 and C3 are not equivalent and need to be specified separately.	Click for larger image
	In the eclipsed conformation, ethane has an S3 axis. Using the images in the table below, click on the H atom in the product which should be coloured red for each operation performed about the S3 axis in C2H6.

Operations	Clickable Image	Corresponding Answer
S3
S32
S33

Note that the S₃ operation is equivalent to neither C₃ nor σ.

Using the S₃ operations, we must rotate the ethane molecule through a total of 720° before it ends up where it started.

Using the images in the table below, click on the H atom in the product which should be coloured red for each further operation performed about the S₃ axis in C₂H₆.

Operations	Clickable Image	Corresponding Answer
S34
S35
S36

Fill in the table below for those S₃ operations you think have equivalent symmetry operations generated by other symmetry elements of ethane. Hence, check all the independent symmetry operations we should assign to S₃.
(Note — There maybe more than one equivalent symmetry operation for a given S₃ operation, if so enter the operations in alphabetical order separated by a comma i.e. a,b )

Symmetry Operations S3 S32 S33 S34 S35 S36

Equivalent Symmetry Element (if any)

Independent Symmetry Operation?

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