AP Notes Chapter 1 Matter & Measurement

1. AP Notes Chapter 1Matter & Measurement matter interactions g mass space L Chemistry is the study of the nature of ______ and its ____________. Matter is anything that has ____ in unit (_) and occupies _____ in unit (_). Matter exists in several different ______ based on the excitation or ____ in unit (_) of the particles. phases heat J

2. 1.1Elements & Atoms atom element • Matter composed of only one type of _____ is classified as an __________. • 114 accepted elements are listed on the periodic table. Names, symbols- some with ______ origins • Elements can be represented by _____, _______, ________ and _______. • Know your element symbols and names! foreign Names, symbols, diagrams models

3. atom characteristic properties • An _____ is the smallest particle of an element that retains the ______________________ of that element. • Elements with similar _________ are grouped in the periodic table. • Characteristics or properties must be definable and even measurable. properties

4. 1.2 Compounds and Molecules chemical compound • When two or more different elements combine together a ________ _________ is formed. • The composition (kind and number) of a atoms in a compound can be represented by a ________ _______. • Compounds may consist of ____ (charged particles) or _________ (discrete units of atoms). chemical formula ions molecules

5. 1.3 Physical Properties Composition • Physical properties can be observed without changing the ___________ of a substance. • Height, weight or mass, size and color are a few physical properties (Table 1.1) • _________ properties depend on amounts and _________ properties do not. Extensive Intensive

6. Temperature average kinetic energy • Temperature is a measure of the _______ ______ ______ . • Different temperature scales, all are talking about the same height of mercury or alcohol. • Derive a equation for converting ºF to ºC • Kelvin scale is an ________ scale there is no temperature below 0K. • Kelvin temperatures = ºC + 273.15 • Kelvin temperatures are _______ related to kinetic energy (the motion of particles). absolute directly

7. Density • Density • Ratio of mass to volume • D = m in units of g V mL • Useful for identifying a compound • Useful for predicting weight • An ________________ does not depend on what the material is • Volume and hence density are temperature dependant Intrinsic property

8. 0ºC = 32ºF 32ºF 0ºC

9. 100ºC = 212ºF 0ºC = 32ºF 0ºC 100ºC 212ºF 32ºF

10. 100ºC = 212ºF 0ºC = 32ºF 100ºC = 180ºF 0ºC 100ºC 212ºF 32ºF

11. 100ºC = 212ºF 0ºC = 32ºF 100ºC = 180ºF 10ºC = 18ºF 5ºC = 9ºF 1ºC = 9ºF 5 0ºC 100ºC 212ºF 32ºF So 5ºC = 1ºF 9

12. (0,32) = (C1,F1) (100,212) = (C2,F2) ºF ºC

13. 1.4 Physical and Chemical Change • Changes in physical properties are called physical changes • Changes in reactants to form new products are caused by a chemical change or chemical reaction • Chemical properties of materials are observable only through a chemical change and represented in a chemical equation

14. Scientific Method • A way of solving problems • Observation- what is seen or measured • Hypothesis- educated guess of why things behave the way they do. (possible explanation) • Experiment- designed to test hypothesis • leads to new observations, • and the cycle goes on

15. After many cycles, a broad, generalizable explanation is developed for why things behave the way they do • Theory – is formed to define a WHY • Also regular patterns of how things behave the same in different systems emerges • Law – is written to explain HOW • Laws are summaries of observations

16. Theories have predictive value. • The true test of a theory is if it can predict new behaviors. • If the prediction is wrong, the theory must be changed. • Theory- why • Law - how

17. Theory (Model) Observations Hypothesis Modify Experiment Prediction Experiment Law

18. 1.5 Classifying Matter • Kinetic-molecular theory • Helps us interpret properties of matter • – matter is composed of tiny particles • – particles are continuously in motion • – in solids they vibrate usually in a regular array • – in liquids & gases more free to move • Kinetic energy – force of motion of particles

19. Observing and describing these particles at the Macroscopic level is the world around us • Attempting to describe these particles at the Submicroscopic or particulate level requires models that represent what we think the particles look like and act like

20. Classifying Matter Matter Heterogeneous Homogeneous Solution Pure Substance Element Compound

21. 1.6 Units of Measurement • Matter must be explainable to others which means that individuals communicating must agree on type and units of measurement or at least be able to convert measures between each others measure • Qualitative – it is blue, (what shade of blue) • Quantitative – it is 4 inches, (well how long is an inch) • A common system of measure is needed

22. Metric System • Every measurement has two parts • Number • Scale (unit) • SI system (le Systeme International) based on the metric system • Prefix + base unit • Prefix tells you the power of 10 to multiply by - decimal system -easy conversions

23. MetricSystem • Base Units - must be definable or derivable • Mass - kilogram (kg) • Length- meter (m) • Time - second (s) • Temperature- Kelvin (K) • Electric current- ampere (amp, A) • Amount of substance- mole (mol)

24. Prefixes • giga- G 1,000,000,000 109 • mega - M 1,000,000 106 • kilo - K 1,000 103 • Hecto - H 1,00 102 • Deka - D 1,0 101 Base Unit grams, Liters, meters100 • deci- d 0.1 10-1 • centi- c 0.01 10-2 • milli- m 0.001 10-3 • micro- m 0.000001 10-6 • nano- n 0.000000001 10-9

25. Deriving the Liter • Liter is defined as the volume of 1 dm3 • gram is the mass of 1 cm3 of water at 25oC where then 1Kg of water is the mass of 1 L of water. Deriving or describing density • Density is the proportional relationship between an objects mass and its volume, D = m/V

26. Mass and Weight • Mass is measure of resistance to change in motion • Weight is force of gravity. • Sometimes used interchangeably • Mass can’t change, weight can

27. 1.7 Using Numerical Information • Systematic error is in same direction each time • Better precision implies better accuracy • You can have precision without accuracy • You can’t have accuracy without precision • How well is a measure known? Significance

28. Accuracy vs. Precision

29. Accuracy Absolute error (AE) = exp - known % Accuracy = 100 - |%AE|

30. Precision Relative error (RE) = exp - average % Precision = 100 - |%RE|

31. Error • Error = experimental – accepted

32. Significant figures • Meaningful digits in a MEASUREMENT • Exact numbers are counted, have unlimited significant figures • If it is measured or estimated, it has sig figs. • If not it is exact. • All numbers except zero are significant. • Some zeros are, some aren’t

33. Which zeroes count? • In between other sig figs does • Before the first number doesn’t • After the last number counts iff • it is after the decimal point • the decimal point is written in • 3200 2 sig figs • 3200.4 sig figs

34. Doing the math • Multiplication and division, same number of sig figs in answer as the least in the problem • Addition and subtraction, same number of decimal places in answer as least in problem.

35. 1.8 Problem Solving • Conversion of a given measurement to a desired quantity by means of mathematical relationship of data • Dimensional Analysis Using the units to solve problems

36. Dimensional Analysis • Use conversion factors to change the units • Conversion factors = 1 • 1 foot = 12 inches (equivalence statement) • 12 in =1= 1 ft. 1 ft. 12 in • Every equality gives 2 conversion factors • multiply by the one that will give you the correct units in your answer.

37. How Many Millimeters in 6.78 inches? • Given: 6.78 in. • Need: millimeters • Connections: 2.54 cm = 1 in. 1cm = 10mm

38. Sample Distance Problems • 11 yards = 2 rod • 40 rods = 1 furlong • 8 furlongs = 1 mile • The Kentucky Derby race is 1.25 miles. How long is the race in rods, furlongs, meters, and kilometers? • A marathon race is 26 miles, 385 yards. What is this distance in rods, furlongs, meters, and kilometers?

39. Sample Mass Problem • Apothecaries (druggists) use the following set of measures in the English system: • 20 grains ap = 1 scruple (exact) • 3 scruples = 1 dram ap (exact) • 8 dram ap = 1 oz. ap (exact) • 1 dram ap = 3.888 g • What is the mass of 1 scruple in grams?

40. Volume Problem How Many Liters in 1.0 Cubic Yard? • Given: 1 yd3 • Need: Liters • Connections: 1 yd = 36 in 2.54 cm = 1 in 1 mL = 1 cm3

41. Sample Speed Problem • Science fiction often uses nautical analogies to describe space travel. If the starship U.S.S. Enterprise is traveling at warp factor 1.71, what is its speed in knots? • Warp 1.71 = 5.00 times the speed of light • speed of light = 3.00 x 108 m/s • 1 knot = 2000 yd/h exactly

42. Sample Problem • The speed of light is 3.00 x 108 m/s. How far will a beam of light travel in 1.00 ns?

43. Density • Density • Ratio of mass to volume • D = m in units of g V mL • Useful for identifying a compound • Useful for predicting weight • An ________________ does not depend on what the material is • Volume and hence density are temperature dependant Intrinsic property

44. Sample Density Problem 1 • An empty container weighs 178.3 g. Filled with carbon tetrachloride (density 1.53 g/cm3 ) the container weighs 317.2 g. What is the volume of the container?

45. Sample Density Problem 2 • A 55.0 gal drum weighs 82.0 lbs. when empty. What will the total mass be when filled with ethanol? density 0.789 g/cm3 1 gal = 3.78 L 1 lb = 454 g