CHEM 105N 1st Edition Lecture 2 Outline of Last Lecture I. Defining ChemistryA. Origination of Chemicals and equipment II. Measurements (Units in Metric and SI Systems)III. Learning Check and Practice QuestionsOutline of Current Lecture I. Definition of Scientific MethodA. Compare and contrast with Standard NumbersII. Measured vs. Known NumbersCurrent LectureI. Defining the Scientific Method:- Is used to write very large or very small numbers- It uses a coefficient and a power of 10- Never estimate a measurement of weight-How to write in the Scientific Method:- The decimal point is placed after the first digit- When moving the decimal to the right, the power of ten is positive- When moving the decimal to the left, the power of ten is negative- Count the number of spaces in which the decimal has moved- Ex: 52000. = 5.2 x 10^4 .00378 = 3.78 x 10^-3- Never estimate a measurement of weight!- It is, however, acceptable to add a second number to a measurement using a ruler. Even if the answer seems to be exactly on the line.-Ex: You may measure a piece of paper to be 12.1 inches long. To add precision, add a zero to the end of your answer= 12.10 in.A. Compare and Contrast with Standard Numbers: - Standard: 128000 m Scientific Notation: 1.28 x 10^5 m- Standard: .00003 km Scientific Notation: 3 x 10^-5 km- Scientific Notation: 7.2 x 10^-3 g Standard: .0072 gII. Measured vs. Known Numbers:- A measuring tool is used to determine a quantity such as height or the mass of an objectThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.- In lengths measured as 5.69, the digits 5 and 6 are KNOWN- The digit 9, is estimated, or UNCERTAIN- All three digits are SIGNIFICANT (will cover in next
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