2. Topic: Temperature & Percent Error & Density again Do Now: Look at test objectives

3. Temperature Scientifically speaking … The definition of temperature: Temperature is measure of average kinetic energy of particles in system

5. Absolute Zero Zero on the Kelvin scale: point at which all matter is said to stop moving

6. World’s Record Cold Temperatures Date ˚F ˚C World (Antarctica) Vostok II 7/21/1983 –129 –89 Verkhoyansk, Russia(Siberia) 2/7/1892 –94 –70 Asia Oimekon, Russia 2/6/1933 –90 –68 Greenland Northice 1/9/1954 –87 –66 N.A. Snag, Yukon, Canada 2/3/1947 –81 –63 U.S. Prospect Creek, Alaska 1/23/1971 –80 –62 U.S. (other than AK) Rogers Pass, Mont. 1/20/1954 –70 –56.5

7. Conversion formulas How can we convert from one temperature scale to another? K = °C + 273 (more precisely 273.15) °C = K – 273 [F = (9/5 °C) + 32]

8. Percent Error     measured value – accepted value  x100% accepted value use absolute value – answer always positive

9. Data table 1.711.451.57 Trial 3 1.691.681.60 Trial 2 1.701.401.54 Trial 1 Student C (g/cm 3 ) Student B (g/cm 3 ) Student A (g/cm 3 ) Students were asked to find the density of sucrose [Sucrose has a density of 1.59 g/cm 3 ]

10. Advantage of % Error Makes it easier to compare data, especially if comparing data from different trials

11. Density Review M DV

12. Looking at this graph again, what is the density of pyrite? HINT: SLOPE What is this graph missing?

13. Scientific Notation product The number is written as the product of two other numbers: not – A number between 1 and 10 (not 10) – and – A power of 10

14. conventional to scientific notation Converting conventional to scientific notation  1exponent positive For numbers  1, the exponent will be positive. Count how many places the decimal is moved. 329  3.29 X 10 2

15. conventional to scientific notation Converting conventional to scientific notation between 0 and 1 exponentnegative For numbers between 0 and 1, the exponent will be negative. Count how many places the decimal is moved. 0.00045  4.5 X 10 -4

16. scientific to conventional Converting scientific to conventional notation If the exponent is positive, the number  1, so move the decimal point right. 3.784 X 10 5  378400

17. scientific to conventional Converting scientific to conventional notation If the exponent is negative, the number is between 0 and 1 so move the decimal point to the left. 2.75 X 10 -3  0.00275