Problem 11E

Explain the difference between a pure substance and a mixture.

Solution 11E: The average value can be calculated as follows 3.15 + 3.12+ 2.98+3.14+3.02+3.09 Thus, the average weight of each bean is = 6 = 18.5 6 = 3.08 g Total weight of the jar having all beans = 2082 g. Weight of empty Jar =6 53 g Thus, weight of all beans =Total weight of the jar having all beans - Weight of empty Jar = 2082 g- 653 g = 1429 g Therefore, Total number of beans in the jar will be Total weight of beans = Average weight of each bean = 1429 g 3.08 g = 463.96 = 464 (significant figures rounded off to 3, this is because the results contains more correct significant figures. Thus the leftmost digit removed is 5 or greater, the preceding number is increased by 1.) Thus, total weight of the jar having beans are four significant figures, whereas average weight of the beans are three significant figures, Therefore, according to the rules of significant figures, for division, the result must contain the fewest significant figures followed by the lowest one. Here fewest significant figures is three which is coming from the average weight of the bean.