Notes for Measurement & Matter Unit

Uncertainty in Measurements Accuracy Precision Error Percent Error

Importance of Measurements Types of measurements 1.Qualitative Examples: 2. Quantitative http://www.cbsnews.com/video/watch/?id=4378494n http://www.space.com/missionlaunches/launches/orbiter_errorupd_093099.htm

Scientific Notation Rules for writing scientific notation: Examples: a. Number must be between 1 and 9 b. Positive exponent = LARGE number c. Negative exponent = SMALL number Examples: 1.9 x 109 is written correctly and is a large number 1900000000 19.8 x 109 is written incorrectly because it is not a number between 1 and 9 1.98 x 10-3 is written correctly and is a small number 0.00198

You will ask yourself ‘why’ Significant Figures – Why?!? In a calculation, it is important to know which digits are significant Last digit is uncertain (estimated or guess) because each person may see it slightly different 1.2311120 You will ask yourself ‘why’ all semester!

*Rules for calculating using sig figs Rounding (pg 40) Adding and subtracting (pg 41) Multiplying and dividing (pg 42)

The universal system modern scientists use for measurement is…

THE METRIC SYSTEM!!!! FORGET THE ENGLISH SYSTEM!!!! The only time you will see the English system is when converting to metric! http://www.youtube.com/watch?v=Omh8Ito-05M

The Systeme International (SI) Unit Symbol Value Kilo- k- 1000 or 103 Meter m Base unit Centi- c- 1/100 or 10-2 Milli- m- 1/1000 or 10-3 Micro- µ- 1/1,000,000 or 10-6 Nano- n- 1/1,000,000,000 or 10-9 1000 m = 1 km 1 L = 1000 mL 1 g = 100 cg

Measuring Length Volume Mass Equipment and units Meniscus Weight vs. mass

Dimensional Analysis You have probably used without knowing it - AKA Factor-label method FINALLY, a reason for algebra How do you find out how many seconds are in a day?

Knowing that: 1 day = 24 hours 1 hour = 60 minutes 1 minute = 60 seconds

So, now we can convert within and outside of the metric system So, now we can convert within and outside of the metric system. All you need to know is the conversion factor. Answer: How many mm are in 1 in? How many cm are in 10 km? How many L are in 5 gallons?

PRACTICE PRACTICAR RÉPÉTER UNIT: something that gives definition to a numerical value, e.g. mile, meters, feet, seconds, etc.   CONVERSION FACTOR: a fraction/equation in which the numerator and denominator represent the same measurement 100 cm = 1 m or 100 cm 1 m *Some common conversion factors: 1 in = 2.54 cm 1 mi = 5280 ft 1 lb = 454 g 1 qt = 2 pt 1 qt = 0.946 L 1 gal = 4 qt 1 cc = 1cm3 = 1 mL

NUMERATOR: the number above the fraction lab   DENOMINATOR: the number below the fraction lab CONSTANT: a known set of quantities INVERT: constants given to you as conversion factors can be flipped around 100 cm or 1 m 1 m 100 cm PER: can refer to the fraction line 60 seconds per minute or 60 sec 1 min

FYI www.chemmybear.com -For study cards!!! http://www.wwnorton.com/college/chemistry/gilbert/index/site_map.htm -Ch. 1 tutorials

Temperature What is temperature? Measured in scales Pg 72 #26 and 28 Absolute zero 1. 0 K 2. -273.15 ºC K = ºC + 273 ºC = K - 273 Pg 72 #26 and 28

Matter & Changes

What is the difference between an ELEMENT and MATTER?

What are the properties of matter? Read pgs 55-60

Matter is anything that has mass and takes up space What’s the matter? Matter is anything that has mass and takes up space Composed of atoms and molecules which act like tiny particles always in motion (kinetic theory) At higher temps, particles move faster or slower? At the same temp, heavier particles move faster or slower?

What’s the matter? Pure substances have only one kind of matter 4 states of matter in the universe Properties of matter Physical Chemical low energy med. energy high energy

States of Matter Solids Liquids Gases Draw 3 bubbles in your notes. Read pg 58-59 and add characteristics to each bubble. Solids Liquids Gases

Why is H2O So Special?

Types of Changes in Matter (p 61-63) Physical Change Chemical Change http://vital.cs.ohio.edu/?page_id=161

Chemical Reactions One or more substances forms new substances Reactants  Products Fe + S  FeS 2H2O2  2H2O + 2O2 yields

Law of Conservation of Mass (p63-64) Mass is neither created not destroyed. Review Example Problem 3-1 Page 65 #6-9 Element cards

Organizing Matter (p 66-67) A mixture is a physical blend of 2+ substances There are 2 types: 1. Heterogeneous 2. Homogeneous Solutions

Organizing Matter (p 68-69) How can these mixtures be separated?

Organizing Matter (p 70-71) What is a pure substance? Element: -Ex: Compound:

Organizing Matter

Physical Properties (p 56) What is a physical property? What is an extensive property? What is an intensive property? http://antoine.frostburg.edu/chem/senese/101/matter/faq/extensive-intensive.shtml

What are physical and chemical changes? Review! What are physical and chemical changes?

What are the techniques chemists use for separating mixtures? http://www.mheducation.ca/school/applets/bcscience7/mixtures/ http://www.teachertube.com/video/separating-a-mixture-demo-355980 http://www.livebinders.com/play/play/481254

Chromatography http://www.sambal.co.uk/chromatography.html - marker chromatography http://bioweb.wku.edu/courses/Biol121/Psynth/Psynth1.asp - paper chromatography of plant pigment