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Bell Work Friday Prepare for Test

Bell Work Friday Prepare for Test. Test Question - Carbon. 1. Atomic Number Atomic Weight Number of Protons Number of Electrons Number of Neutrons. Percent Composition from Electrolysis Lab. Height of hydrogen _____________ Height of oxygen ___________ Total __________

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Bell Work Friday Prepare for Test

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  1. Bell Work Friday Prepare for Test

  2. Test Question - Carbon • 1. Atomic Number • Atomic Weight • Number of Protons • Number of Electrons • Number of Neutrons

  3. Percent Composition from Electrolysis Lab • Height of hydrogen _____________ • Height of oxygen ___________ • Total __________ • Part H / Whole x 100 = __________% H • Part O / Whole x 100 = __________% O • Does your answer support the formula for water? Explain how it supports the formula. If not, explain the experimental errors that could cause a problem.

  4. Today’s ElementUutUnuntrium • Periodic Table Placement • Group 3A or 13 • Period 7 Video: Periodic Table of Videos

  5. Find the Atomic Weight for MgSO4 • Bell work composition book

  6. Water: Separation by Electrolysis Video of Electrolysis: Water to Hydrogen and Oxygen

  7. Atomic Mass of a Compound • H2O Try these • CO2 • C6H12O6 H2 1.01 x 2 = 2.02 O 16 x 1 = 16.00 Add totals 2.02 + 16.00 18.02 1.01 + 1.01 + 16 = 18.02

  8. Practice – Finding Atomic Mass • CO2 C 12.01 x 1 = 12.01 O2 16 x 2 = 32.00 Add totals 12.01 + 32.00 44.01

  9. Practice – Finding Atomic Mass • C6H12O6 C6 12.01 x 6 = 72.06 H12 1.01 x 12 = 12.12 O2 16 x 6 = 96.00 Add totals 72.06 12.12 +96.00 108.18

  10. Percent Composition of Mass for Mixtures • A 6g mixture of sulfur and iron is separated using a magnet. Data Sulfur (S) Iron (Fe) 5g 1g • Calculate the percent composition of S and Fe.

  11. Percent Composition of Mass for Mixtures • A 6g mixture of sulfur and iron is separated using a magnet. Data Sulfur (S) Iron (Fe) 5g 1g • Calculate the percent composition of S and Fe. Part / Whole x 100 = % composition Sulfur: 5g/6g x 100 = Iron : 1g/6g x 100 =

  12. Percent Composition of Mass for Mixtures • A 6g mixture of sulfur and iron is separated using a magnet. Data Sulfur (S) Iron (Fe) 5g 1g • Calculate the percent composition of S and Fe. Part / Whole x 100 = % composition Sulfur: 5g/6g x 100 = 83.33% S Iron : 1g/6g x 100 = 16.66% Fe

  13. Use Percent Composition to find the composition of a compound • Use the periodic table to find the compound’s percent composition of each element. • List the atomic weight of each element in the compound • Note how many of each type of atom is in the compound • Add it all up to get the atomic weight of the whole compound

  14. Atomic Mass of a Compound • H2O Try these • CO2 • C6H12O6 H2 1.01 x 2 = 2.02 O 16 x 1 = 16.00 Add totals 2.02 + 16.00 18.02 1.01 + 1.01 + 16 = 18.02

  15. Practice – Percent Composition H2O part / whole x 100 = % composition % composition of H % composition of O

  16. Practice – Percent Composition CO2 part / whole x 100 = % composition % composition of C % composition of O

  17. Practice – Percent Composition C6H12O6 part / whole x 100 = % composition % composition of C % composition of H % composition of O

  18. Law of Conservation of Mass • Mass is neither created nor destroyed in any process. It is conserved. Mass reactants = Mass products 2H2O + electricity yields 2H2 + O2

  19. Isotopes • The atomic weight found on the periodic table is based on the average weight of all the isotopes of the element • Isotope – atoms of the same element with the same number of protons but different numbers of neutrons • M&M activity

  20. Writing Isotopes

  21. Reading Isotopes Mass number - the sum of the protons and neutrons

  22. Isotopes of Hydrogen

  23. Write Isotopes for Iron

  24. More isotopes Argon 36, Argon 37…

  25. M&Mium Isotope Activity

  26. http://www.chem.memphis.edu/bridson/FundChem/T07a1100.htm

  27. S.I.Units • http://2012books.lardbucket.org/books/general-chemistry-principles-patterns-and-applications-v1.0/section_05.html#averill_1.0-ch01_s09_s01_s02_t02

  28. http://chemwiki.ucdavis.edu/Physical_Chemistry/Atomic_Theory/The_Mole_and_Avogadro's_Constanthttp://chemwiki.ucdavis.edu/Physical_Chemistry/Atomic_Theory/The_Mole_and_Avogadro's_Constant

  29. Measurements and Calculations Where to Round Song

  30. Steps in the Scientific Method • 1. Observations • - quantitative • - qualitative • 2. Formulating hypotheses • - possible explanation for the observation • 3. Performing experiments • - gathering new information to decide whether the hypothesis is valid

  31. Outcomes Over the Long-Term • Theory (Model) • - A set of tested hypotheses that give an overall explanation of some natural phenomenon. • Natural Law • - The same observation applies to many different systems • - Example - Law of Conservation of Mass

  32. Law vs. Theory • A law summarizes what happens • A theory (model) is an attempt to explain why it happens.

  33. Nature of Measurement Measurement - quantitative observation consisting of 2 parts • Part 1 - number • Part 2 - scale (unit) • Examples: • 20grams • 6.63 x 10-34Joule seconds

  34. The Fundamental SI Units(le Système International, SI)International System of Unitsa system of measurement units agreed on by scientists to aid in the comparison of results worldwide.

  35. SI Units

  36. Metric PrefixesCommon to Chemistry

  37. Metric Prefixes and Conversion Examples

  38. Uncertainty in Measurement • A digit that must be estimated is called uncertain. A measurement always has some degree of uncertainty.

  39. Why Is there Uncertainty? • Measurements are performed with instruments • No instrument can read to an infinite number of decimal places Which of these balances has the greatest uncertainty in measurement?

  40. Precision and Accuracy • Accuracyrefers to the agreement of a particular value with the truevalue. • Precisionrefers to the degree of agreement among several measurements made in the same manner. Precise but not accurate Precise AND accurate Neither accurate nor precise

  41. Types of Error • Random Error(Indeterminate Error) - measurement has an equal probability of being high or low. • Systematic Error(Determinate Error) - Occurs in the same directioneach time (high or low), often resulting from poor technique or incorrect calibration.

  42. Rules for Counting Significant Figures - Details • Nonzero integersalways count as significant figures. • 3456has • 4sig figs.

  43. Rules for Counting Significant Figures - Details • Zeros • -Leading zeros do not count as significant figures. • 0.0486 has • 3 sig figs.

  44. Rules for Counting Significant Figures - Details • Zeros • -Captive zeros always count as significant figures. • 16.07 has • 4 sig figs.

  45. Rules for Counting Significant Figures - Details • Zeros • Trailing zerosare significant only if the number contains a decimal point. • 9.300 has • 4 sig figs.

  46. Rules for Counting Significant Figures - Details • Exact numbershave an infinite number of significant figures. • 1 inch = 2.54cm, exactly

  47. Sig Fig Practice #1 How many significant figures in each of the following? 1.0070 m  5 sig figs 17.10 kg  4 sig figs 100,890 L  5 sig figs 3.29 x 103 s  3 sig figs 0.0054 cm  2 sig figs 3,200,000  2 sig figs

  48. Rules for Significant Figures in Mathematical Operations • Multiplication and Division:# sig figs in the result equals the number in the least precise measurement used in the calculation. • 6.38 x 2.0 = • 12.76 13 (2 sig figs)

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