Unit 1 – Measurement Lesson 1 – Scientific Notation

1. Unit 1 – MeasurementLesson 1 – Scientific Notation Do Now: Get your calculators out. Yeah, that’s about it. Music: Bill Nye the Science Guy Book Section: 2-3

2. It’s Time to Begin Chemistry! • So we’re starting with… math? • Yes. Honors Chemistry (aka REAL chemistry) is math-based, so you need to learn how to do math like the real scientists do. • The first step in this process is to make sure that you understand scientific, or exponential notation.

3. It’s Time to Begin Chemistry! • So we’re starting with… math? • Yes. Honors Chemistry (aka REAL chemistry) is math-based, so you need to learn how to do math like the real scientists do. • The first step in this process is to make sure that you understand scientific, or exponential notation.

4. Your Book is Boring • Ahem… “In scientific notation, numbers are written in the form M x 10n, where the factor M is a number greater than or equal to 1 but less than 10 and n is a whole number.”

5. Scientific Notation • One thing you’ll understand about scientists is that when they write, they like to be very dense. • This is a result of publishing in journals, where one page might cost $300,000… so you want to get as much information on that page as possible. • So, numbers must also be dense. • Instead of writing 540,000,000, this getsrewritten as 5.4 x 108. Both numbers meanthe same thing, and when you do operations(addition, etc.) with them, they should betreated no differently from each other. Science is one of the most well-known journals. Creative name.

6. The Rules of Scientific Notation • The first number can only have one non-zero digit before the decimal point. • 5.4 x 108 – • 10.3 x 103 – • The exponent must be a whole number power of 10. • 2.3 x 10.344 just doesn’t fly. So don’t do it.

7. Converting to Scientific Notation • The power of ten, (ex. 103) is the number of tens that the number is multiplied by. • Ex: 103 = 10 x 10 x 10 = 1,000 • If your exponent is positive, move the decimal point to the right that many places. If negative, move to the left. • 2.4 x 102 = 240 • 2.4 x 10-2 = 0.024

8. Why is this necessary? • In this class in particular, there’s a nice, big number that takes over this class in about two months: the mole. • 1 triple = 3 • 1 dozen = 12 • 1 mole = 6.022 x 1023 … yeah, that’s really big. • 602,200,000,000,000,000,000,000, to approximate it. • So, learning scientific notation and using it will help you later on. • The mole is a big number because it allows us to count the number of atoms in something. • Visual Demo – A mole of water

9. Alas, there is hope! • Your calculator has the ability to perform scientific notation very easily. • Find the EXP or EE button on your calculator. • EE stands for Engineering Exponent, or scientific notation. • Try putting 3.08 x 10-3 into your calculator. • Hit 3.08, then the EXP/EE button, then -3. (Negative, not minus) • 3.08E-3 is what you should see. This is the same as 3.08 x 10-3. • On assignments, please use the standard format.

10. Operations w/ Scientific Notation • I don’t believe in unnecessary torture (only the necessary kind), so I will expect you do perform scientific notation operations on your calculator. • Example: (5.23 x 106)(7.1 x 10-2) • Try using the EE method. It makes life easier. • Keep trying until you get 3.7 x 105.

11. Operations w/ Scientific Notation • I don’t believe in unnecessary torture (only the necessary kind), so I will expect you do perform scientific notation operations on your calculator. • Example: (5.23 x 106)(7.1 x 10-2) • Try using the EE method. It makes life easier. • Keep trying until you get 3.7 x 105.

12. Video • I really like to have a video in every class, but all the ones I found on scientific notation were boring. So, here’s a video that might get you thinking about “adolescence.” • Homework 1-1: #1-3 • Quiz 1-1 on Monday (5 points on practice) • The question(s) will be completely random. If you are absent, you must turn in the completed problems for credit.