Chapter 1 – Introduction: Matter & Measurements

1. Chapter 1 – Introduction: Matter & Measurements Learning Targets• Distinguish between chemical and physical changes and properties. • Know the states of matter and characteristics of each. • Understand the difference between elements, molecules, compounds, and mixtures. • Know the various techniques for separating the components of a mixture, and the principle upon which each of these operates. • Be familiar with the units of the metric system and the temperature scales. • Understand the concept of density and be able to answer all questions, both conceptual and mathematical, related to density. • Be able to convert measurements, especially within the metric system, by using dimensional analysis. • Determine the number of significant figures in a measurement and be able to express the results of a calculation with the proper number of significant figures.

2. Chapter 2 – Atoms, Molecules, and Ions Learning Targets• Understand the atomic theory, and how it relates to theories of chemistry. • Distinguish between protons, neutrons, and electrons, and be able to describe the composition of an atom of any particular element in terms of these subatomic particles. • Understand the difference between isotopes, as well as the two types of notations used with them. • Be aware of who discovered each subatomic particle and have an idea of how they did it. • Know the difference between an atom, and ion, and a molecule. • Have a basic knowledge of the periodic table, which includes being able to predict whether an element is a metal or a nonmetal, and what will be the probable charge of its ion • Know that the given atomic mass of an element is the weighted average of the atomic masses of all isotopes of that element. Be able to perform all related calculation. • Be able to give the name and/or formula for any given compound.

3. Key Words – Chapter 1 • Matter • Molecule • Distillation • Pure substance • Compound • Solution • Physical properties • Intensive properties • Physical change • Density • Atom • Filtration • Chromatography • Element • Mixture • Chemical properties • Extensive properties • Chemical change • Significant Figures

4. Key Words – Chapter 2 • Atom • Ion • Proton • Neutron • Electron • Atomic number • Nuclide • Group • Period • Anion • Molecule • Isotope • Mass Number • Atomic Weight • Metal • Nonmetal • Metalloid • Molecular Formula • Empirical Formula • Cation

5. Section 1: Separation TechniquesPages 11-12 RBQs # 15,16,78,79 • A mixture is a combination of two or more substances in which each substance retains its own chemical identity • Because they retain their chemical identities, a mixture can be separated by physical means, as opposed to a compound • Three common means of separating mixtures are filtration, distillation, and chromatography

6. Section 1: Separation TechniquesPages 11-12 RBQs # 15,16,78,79 • Filtration:

7. Section 1: Separation TechniquesPages 11-12 RBQs # 15,16,78,79 • Distillation:

8. Section 1: Separation TechniquesPages 11-12 RBQs # 15,16,78,79 • Paper Chromatography

9. Section 1: Separation TechniquesPages 11-12 RBQs # 15,16,78,79 • Gas Chromatography

10. Section 2: Units & Measurement Pages 13-17 RBQs # 19-25,29,30 • Lab data can be either quantitative or qualitative • Qualitative: • Quantitative:

11. Section 2: Units & Measurement Pages 13-17 RBQs # 19-25,29,30 • Quantitative data (measurements) MUST include a number and unit • The units in chemistry are called the SI Units; these are the internationally agreed upon set of units

12. Section 2: Units & Measurement Pages 13-17 RBQs # 19-25,29,30 • The SI base units are modified using metric prefixes to make the number more manageable

13. Section 2: Units & Measurement Pages 13-17 RBQs # 19-25,29,30 • The instruments used to make measurements have limitations which leads to estimations being made with measurements

14. Section 2: Units & Measurement Pages 13-17 RBQs # 19-25,29,30 • When a measurement is made, all certain digits are recorded, and the final estimated digit is uncertain digit • Every measurement will contain all certain digits and one estimated uncertain digit; combined, these digits are known as the significant figures • To make sure the proper number of digits is always given, the rules of significant figures are applied to numbers and calculations

15. Section 2: Units & Measurement Pages 13-17 RBQs # 19-25,29,30

16. How many sig figs are in the measurement 4.003 m?

17. How many sig figs are in the number 6.023 x 1023?

18. How many sig figs are in the number 5000?

19. Section 2: Units & Measurement Pages 13-17 RBQs # 19-25,29,30

20. Do this! 1.05 x 10-3 ÷ 6.135 =

21. Do this! 21- 13.8 =

22. Section 2: Units & Measurement Pages 13-17 RBQs # 19-25,29,30 • An important technique for problem solving is called dimensional analysis which uses conversion factors • This technique is used to convert a quantity to an equivalent quantity, but with a different unit • For example, dimensional analysis could show 3 dollars are equal to 12 quarters; same amount of money, different units

23. Section 2: Units & Measurement Pages 13-17 RBQs # 19-25,29,30 • The first thing to know is the numerical relationship between the starting quantity and the desired quantity • For example, if the number of meters in a given number of inches is needed, one must know the number of inches in a meter (or vice versa) • There are 39.37 inches in 1 meter, and as a conversion factor, this information could be written as seen below:

24. Section 2: Units & Measurement Pages 13-17 RBQs # 19-25,29,30 • The conversion factor will always be a fraction, and once it is determined, the conversion factor is arranged so that the given unit is eliminated and replaced with the desired unit • For example, if the questions wants to know the number of meters in 69.5 inches:

25. Do This! A pencil is 7.000 in long. What is this length in cm? (1 in = 2.54 cm)

26. Do This! An N2 molecule moves at 515 m/s. What is this speed in mi/hr?

27. Section 3: Atomic Structure & MassPages 35-45 RBQs # 13-21,23,24 • The atom is the basic building block of matter; it is defined as the smallest unit of an element that retains the properties of that element→ An atom of gold is the smallest piece of gold that is yellow and shiny→ An atom of oxygen is the smallest unit of oxygen that we can breathe • The concept of the atom has been around for thousands of years, but this idea has only been backed by scientific experimentation since the 1700’s • The atom’s existence and structure was confirmed and determined through a number of experiments by several scientists

28. Section 3: Atomic Structure & MassPages 35-45 RBQs # 13-21,23,24 • All matter is composed of extremely small particles called atoms • Atoms of a given element are identical • Atoms cannot be created, destroyed, or divided • Atoms combine in whole number ratios to form compounds • In chemical reactions, atoms are separated, rearranged and combined John Dalton. Smart, but not always right.

29. Section 3: Atomic Structure & MassPages 35-45 RBQs # 13-21,23,24 • J.J. Thompson did most of the heavy lifting in the discovery of electrons with the cathode ray tube

30. Section 3: Atomic Structure & MassPages 35-45 RBQs # 13-21,23,24 • Ernest Rutherford was all up in the nucleus with the gold foil/alpha particle experiment

31. Section 3: Atomic Structure & MassPages 35-45 RBQs # 13-21,23,24 • Another thing learned through all this research was that all atoms of a given element do not have the same mass • Isotopes are atoms of a given element that have different masses; the difference in these masses results from different numbers of neutrons • An atom of a specific isotope is called a nuclide

32. Section 3: Atomic Structure & MassPages 35-45 RBQs # 13-21,23,24 • These different nuclides are detected and counted using a technique called mass spectrometry which can be used to identify unknowns and determine atomic masses

33. Section 3: Atomic Structure & MassPages 35-45 RBQs # 13-21,23,24 • The result is a mass spectrum such as this:

34. Section 3: Atomic Structure & MassPages 35-45 RBQs # 13-21,23,24 • The y-axis will have a scale that can be read, but let’s just let the computer give us the numbers • Based on the height of each peak, the amount of each isotope/nuclide in the sample is determined • The spectrum above shows 100 nuclides with a mass of 12 and 23 nuclides with a mass of 10

35. Section 3: Atomic Structure & MassPages 35-45 RBQs # 13-21,23,24 • The mass spectrum data can also be given in the form of percent abundance

36. Section 4: Periodic Table, Molecules, IonsPages 46-56 RBQs # 29-32,36-38,41-50 • The elements are arranged by increasing atomic number • Elements are in groups (columns) and periods (rows) • Elements are also categorized as metals, metalloid, nonmetals, and noble gases

37. Section 4: Periodic Table, Molecules, IonsPages 46-56 RBQs # 29-32,36-38,41-50 • The real fun starts when elements combine to form compounds • Sometimes these compounds are called molecules

38. Section 4: Periodic Table, Molecules, IonsPages 46-56 RBQs # 29-32,36-38,41-50 • Once metals get involved, we have ionic compounds

39. Section 4: Periodic Table, Molecules, IonsPages 46-56 RBQs # 29-32,36-38,41-50 • Ion charges can be predicted using the periodic table

40. Section 5: Chemical NomenclaturePages 56-65 RBQs # 51-66 • Determining the names and formulas of a chemical compound is kind of a big deal in chemistry • There are four types of compounds that each have their own rules when it comes to nomenclature • Ionic compounds, covalent/molecular compounds, acids, and organic compounds

41. Section 5: Chemical NomenclaturePages 56-65 RBQs # 51-66 • For ionic compounds, just give the name of each ion, with the cation always first • The name of monatomic cation is the same as the element • The only exception is when the monatomic cation can have multiple charges, like most transition metals

42. Section 5: Chemical NomenclaturePages 56-65 RBQs # 51-66 • The name of monatomic anion keeps the same base as the element , but the ending changes to –ide • The name of a polyatomic ion never changes

43. Name this! K2SO4

44. Name this! Ba(OH)2

45. Name this! FeCl3

46. Formula This! Ammonium Sulfide

47. Formula this! Cobalt(II) Nitrate

48. Formula This! Chromium(III) Oxide

49. Section 5: Chemical NomenclaturePages 56-65 RBQs # 51-66 • Binary covalent compounds are named using prefixes to indicate the number of each element present in each molecule • The name of the compound always ends in –ide • The prefix mono- is never used with the first element

50. Name This! SO2