I will be constantly providing some tips to highlight some common mistakes made by students that prevented them in scoring?for Chemistry Examinations.
Today, i would like to cover Significant Figures in Mole Calculations for Chemistry. I was coaching several students for last week and noticed that they are not very certain on the use of significant figures when they leave their final answers for Mole Calculations. Many times, we see students having great understanding and strength in Mole Calculations, but they lost valuable marks due to the inaccuracy of the final answers.
–> Significant figures are NOT the same as Decimal places. For example, 127.09 is to two decimal places but to five significant figures. Zeros before any definite numbers do not count as significant figures, so 0.00000048 is to two significant figures.
–> When doing calculations, your final answers to each section should be to the correct number of significant figures. Generally, it should be to the same number of significant figures as the data given in the question. You may get penalized if you write your answers to an excess number of significant figures, e.g. 3.26758 instead of 3.27.
Something Simple yet Important to note.
Hope this will galvanize you to score more full marks in those calculation questions in Chemistry.