- Tigures Is Uncertain In A Number That Ends With A Zero To The Left Of The Decimal Point Location The Zeros In The Measu 1 (53.63 KiB) Viewed 124 times
- Tigures Is Uncertain In A Number That Ends With A Zero To The Left Of The Decimal Point Location The Zeros In The Measu 2 (53.63 KiB) Viewed 124 times
- Tigures Is Uncertain In A Number That Ends With A Zero To The Left Of The Decimal Point Location The Zeros In The Measu 3 (32.72 KiB) Viewed 124 times
Tigures is uncertain in a number that ends with a zero to the left of the decimal point location. The zeros in the measurement 1,300 grams could be significant or they could simply indicate where the decimal point is located. The ambiguity can be resolved with the use of exponential notation: 1.3 X 10' (two significant figures), 1.30 x 10° (three significant figures, if the tens place was measured), or 1.300 X 10(four significant figures, if the ones place was also measured). In cases where only the decimal-formatted number is available, it is prudent to assume that all trailing zeros are not significant. -Significant figures: clearly result of measurement 1300 g u These zeros could be significant (measured), or they could be placeholders When determining significant figures, be sure to pay attention to reported values and think about the measurement and significant figures in terms of what is reasonable or likely when evaluating whether the value makes sense. For example, the official January 2014 census reported the resident population of the US as 317,297,725. Do you think the US population was correctly determined to the reported nine significant figures, that is, to the exact number of people? People are constantly being born, dying, or moving into or out of the country, and assumptions are made to account for the large number of people who are not actually counted. Because of these uncertainties, it might be more reasonable to expect that we know the population to within perhaps a million or so, in which case the population should be reported as 3.17 x 10% people. Significant Figures in Calculations A second important principle of uncertainty is that results calculated from a measurement are at least as uncertain as This OpenStax book is available for free at
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a) A chemical reaction is given below. Write the rate of the reaction with respect to each reactant and product. [2 marks] Fe2O3 + 3C02Fe + 3CO2 b) A Kinetic experiment gives the following data for the following reaction. Find the average rate of the reaction between t=0 sec to t=5 sec and also between t= 5 sec and t= 10 sec. [ 2 Marks) OCH+OF+CI- 1.2 0.8 0.6 0.4 0.3 [OCIM t (sec) 5 10 15 20