What is the percentage error for a mass measurement of 17.7g, given that the correct value is 21.2g?

16.5% First, determine the total error by subtracting the accepted value from the value you measured. e = 17.7 - 21.2 = -3.5 Then divide the error by the accepted value. e = -3.5/21.2 = -0.165 = -16.5% Sometimes it's useful to keep track of if the error is positive, or negative. But for this case, we'll just go with the positive percentage. So the answer is 16.5% Key thing to remember. You divide by the CORRECT value to get the percentage.

For cyclohexane compounds drawn in a chair conformation:   -axial bonds are vertical  -equatorial bonds are parallel to two bonds within the ring.  thus, as i assume the chair conformation is drawn:   -the x group is in an axial position, as are the five other vertical bonds.  -three axial bonds are on the top face of the ring  -the other three axial bonds are on the bottom face  the position of the second substituent on each ring carbon is equatorial.  gauche groups must be on an adjacent carbon such as carbon 6 and carbon 2, and also gauche groups are rotated by 60 degrees relative to each other.  drawing the newman projections for c1–c2 and c1–c6 aids in visualizing the groups that are gauche to the y group on c1.  click this link and watch some academic videos that may you more understand the topic 

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