U1D8: Scientific Notation: How to write very large and very small numbers Agenda: 1.Complete Al Foil Lab data collection (15 minutes) 2.Significant figure Review WS and Checkpoint 3.You will be able to write very large and very small numbers proficiently. 4.Review 1 Do Now: 1. Density Lab out: Complete Measures. 2. Complete Density Lab Do Now (turn over when done)

Aluminum Foil Lab Due Monday (Day 11)…Don’t Forget… People still owe Measurement Lab , Safety Lab and Sci Method Lab  5

What is the rule if… kg = 3 x kg m = 1.5 x 10 7 m L = 4.35 x 10 5 L g = 9.73 x g Rule: Pos exponent = large number Neg exponent = small number (less than 1) # btwn 1 and 10 (w/ approp sig fig) Base number = 10 6

Scientific Notation Scientists like to be ‘efficient’, and have an easier way to express those loooong numbers 7

Scientific Notation SCIENTIFIC NOTATION: Expressing a number as a multiple of a power of ten. Used to take looooong numbers and compress them so that they can be more easily calculated m/s  3 x 10 8 m/s 8

Handling Large Numbers Take the significant figures from the number, put them into the form N.NNN X 10 x x, – Place a decimal so the # is between 1 and 10 – “x” represents the number of decimal places moved Include ALL OF THE SIG FIGS! 9

. So… World Population: people In sci notation: _____________________ Practice: Sci Notation Ō

What if you’re given Sci. Not.???? Put in decimal form x x x x 10 9 * remember rules of Sig Figs 11

Handling small numbers Sig figs written as a number between 1 and 10 Exponent is NEGATIVE x 10 –x (moved from the left) Practice: Sci Notation

Handling small numbers (must include the 0 because it is a sig fig) Count from the 2 back to the 0 in the one’s place…. Three places The 3 will be negative and we get… 2.0 x

Converting to decimals Reverse procedure 8 x is 3 places from the ones place Put in decimal form x ________________________ x _______________________ x ________________________ x ________________________ * remember rules of Sig Figs 14

Lets play; “Which number is larger?!” A: 2.0 x 10 2 or B: 2.0 x Positive exponents are larger than negative ones (they’re decimals!) A: 1.3 x 10 3 or B: 1.3 x 10 5 For positives, the bigger the exponent, the bigger the number A: 2.6 x or B: 2.6 x For negatives, the smaller the exponent, the larger the number 15

Right or Wrong? What’s the error?? x x x x x x

Complete Scientific Notation WS Have me check your answers when done, then move onto Practice #4 17

Take out Practice Packet Number Scientific Notation A) Convert each of the following into scientific notation:

19 Scientific Notation Standard Decimal Notation X X X X B) Convert each of the following into standard decimal notation:

C) Ksp is a measurement of the solubility of a salt. The larger the value of Ksp is, the more salt can dissolve in water. 1)4.3 X ) 5.7 X ) 9.8 X ) 3.2 x a) Which of the following Ksp values would indicate the salt with the highest solubility? _______ b) Which of the following Ksp values would indicate the salt with the lowest solubility? _______ c) Explain how you answered a and b. 20

Tonight: Complete WS: Scientific Notation! Density Lab due Day 11 21