University:
University of Arkansas
Course:
CHEM 1053 | Chemistry in the Modern World
Academic year:

2023
Views:

123

Pages:

1
Author:

madeleinejames20

In this example problem, we will determine the number of significant figures we can keep in an addition calculation that has numbers in scientific notation. Our problem reads: complete the calculation, giving your answer to the correct number of significant figures. The calculation is: 4.56 x 10^(-3) + 1.15 x 10^(-2) + 0.124 + 0.920 When we add or subtract numbers that are in scientific notation, we need to rewrite all of our numbers so that they have the same exponent. Since two of our numbers are in decimal form which have an exponent of zero, we're going to rewrite 4.56 x 10^(-3) into decimal form, which is 0.00456. We'll do the same thing for 1.15 x 10^(-2), which is 0.0115. Now we can add the numbers, lining up the decimal point. When we add these numbers together, we get 1.050006. Now, we have to determine how many significant figures we can keep for addition and subtraction. We have to look with respect to the decimal point: which number is least significant? Both 0.124 and 0.920 are represented to the nearest thousandth, which means our answer can only be represented to the nearest thousandth. So, our answer is 1.050.