2.6 cm+ 6.12 cm^Total =
12.28 cm =
12.3 cmExplanation: One of the quantities added has only one decimal place. Therefore,
the answer should be rounded to only one decimal place.
Example 2
Problem
Unrounded answer
Answer rounded to the correct number of significant figures3.514 cm^−2.13 cm^Difference =
1.384 cm =
1.38 cmExplanation: One of the quantities has only two decimal places. Therefore, the
answer should be rounded to only two decimal places.
CHAPTER SUMMARY
The following terms summarize all the concepts and ideas that were introduced in
this chapter. You should be able to explain their meaning and how you would use
them in chemistry. They appear in boldface type in this chapter to draw your
attention to them. The boldface type also makes it easier for you to look them up if
you need to. You could also use Internet search engines like google.com on your
computer to get a quick and expanded explanation of these terms, laws, and
formulas.
accuracy
activation energy
calorie
Celsius
chemical change
chemical property
compound
density