Welcome to AP Chemistry What is AP Chemistry

Welcome to AP Chemistry

What is AP Chemistry? It is several things: – Equivalent of 1 year college inorganic chemistry class – A class that will prepare you for a test • May 4, 2015 – Hard work – A wonderful way to spend your day l Now on to the details l

Rules and Procedures I like the term “expectations” l. I expect a commitment to excellence and total immersion in the details of chemistry! l. I will endeavor to treat everyone with DIGNITY, DECENCY, & RESPECT and expect no less from you! l. I expect HONESTY! l. I expect everyone will take care of equipment, furnishing, and the room!

Rules and Procedures l MAKE-UP WORK: – It is your responsibility to make up all the work you missed. You have the same number of days that you were absent to turn in the missing work. – Pick up any missing work, and notes during Chemistry Clinic. – If you miss a test or quiz, it must be made up during a single visit to Chemistry Clinic.

Rules and Procedures l TARDIES – read the school policy – don’t be late and you don’t have a problem. l No Food, Drink Or Gum In Class LATE WORK – I don’t accept late homework. I do accept other assignment late (10% off each day) l l

Rules and Procedures PASSES: Since every minute of class time is valuable, hall passes will be given only on an emergency basis. l No Mole Bucks issued or used in AP l

Rules and Procedures LAB- Because of the importance of safety in the lab, violation of laboratory safety rules and procedures may result in loss of lab privileges. l You Break it – you pay for the replacement include shipping and handling. l

Grading l Grade breakdown 1. Homework / Classwork / Quizzes & Shakhashiri 10% 2. Labs & Lab Reports 25% 3. POGILS & Virtual Chem. Labs 25% 4. Tests 40%

What you need for class DAILY Paper l Pencil & pen l Calculator- Scientific l Zumdahl Text l Lab Notebook l

Any questions? l Lets get started

Significant figures Meaningful digits in a MEASUREMENT l If it is measured, it has sig figs. l If not it is exact. l All numbers except zero are significant. l Some zeros are, some aren’t l See the H Chem handout for examples and more specific rules. l l USE SIG FIG ON EVERYTHING, ALL SEMESTER

Which zeroes count? In between other sig figs does l Before the first number doesn’t l After the last number counts if there is a decimal point l Examples – 3200 2 sig figs l – 3200. 4 sig figs

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

Scientific Method Steps. l A way of solving problems – Observation (2 general types): 1. Qualitative (color, precipitate, warm) 2. Quantitative (involves number w/ units) – Hypothesis - possible explanation – Experiment - test hypothesis – Reiterations – repeat the process

Scientific method. After many cycles, a broad, generalizable explanation is developed for why things behave the way they do with considerable evidence = Theory (Model) l A concise verbal or mathematical statement summarizes a variety of observation = Law l Laws are summaries of observations l

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

Observations Hypothesis Theory (Model) Modify Experiment Prediction Law Experiment

Metric System l Every measurement has two parts 1. Number 2. Scale (unit) l SI system (le Systeme International) based on the metric system l Prefix + base unit l Prefix tells you the power of 10 to multiply by - decimal system -easy conversions

Metric System l Base Units – Mass - kilogram (kg) – Length- meter (m) – Time - second (s) – Temperature- Kelvin (K) – Electric current- ampere (amp, A) – Amount of substance- mole (mol) Chemistry generally uses gram & millimeter

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

Uncertainty Basis for significant figures l All measurements are uncertain to some degree l Precision- how repeatable l Accuracy- how correct - closeness to true value. l Random error - equal chance of being high or low- addressed by averaging measurements - expected l

Uncertainty Systematic error- same direction each time - Want to avoid l Better precision implies better accuracy l You can have precision without accuracy l You can’t have accuracy without precision l

Dimensional Analysis Using the units to solve problems

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

Examples 11 yards = 2 rod l 40 rods = 1 furlong l 8 furlongs = 1 mile l The Kentucky Derby race is 1. 25 miles. How long is the race in rods, furlongs, meters, and kilometers? l A marathon race is 26 miles, 385 yards. What is this distance in rods, furlongs, meters, and kilometers? l

Examples 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? l Warp 1. 71 = 5. 00 times the speed of light l speed of light = 3. 00 x 108 m/s l 1 knot = 2000 yd/h exactly l

Examples Apothecaries (druggists) use the following set of measures in the English system: l 20 grains ap = 1 scruple (exact) l 3 scruples = 1 dram ap (exact) l 8 dram ap = 1 oz. ap (exact) l 1 dram ap = 3. 888 g l 1 oz. ap = 1 oz. troy = 28. 349 grams l What is the mass of 1 scruple in grams? l

Examples l The speed of light is 3. 00 x 108 m/s. How far will a beam of light travel in 1. 00 ns?

Temperature and Density

Temperature l A measure of the average kinetic energy l WE WILL USE ONLY CELSIUS IN AP Different temperature scales, all are talking about the same height of mercury. l Derive a equation for converting ºF toºC l

0ºC = 32ºF 0ºC 32ºF

100ºC = 212ºF 0ºC = 32ºF 0ºC 100ºC 212ºF 32ºF

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

100ºC = 212ºF 0ºC = 32ºF 100ºC = 180ºF 1ºC = (180/100)ºF 1ºC = 9/5ºF 0ºC 100ºC 212ºF 32ºF

(0, 32)= (C 1, F 1) ºF ºC

(0, 32) = (C 1, F 1) (120, 212) = (C 2, F 2) ºF ºC

Density Ratio of mass to volume l D = m/V l Useful for identifying a compound l Useful for predicting weight l An intrinsic property- does not depend on what the material is l

Density Problem l An empty container weighs 121. 3 g. Filled with carbon tetrachloride (density 1. 53 g/cm 3 ) the container weighs 283. 2 g. What is the volume of the container?

Density Problem l A 55. 0 gal drum weighs 75. 0 lbs. when empty. What will the total mass be when filled with ethanol? density 0. 789 g/cm 3 1 gal = 3. 78 L 1 lb = 454 g

Classification of Matter Def. Matter is anything that occupies space and has mass l 3 States: Solid, Liquid, and Gas l 2 Types of Mixtures: – Homogeneous – parts are not easily distinguishable, not easily separated, example: solution – Heterogeneous – visibly distinguishable parts l

Classification of Matter Pure Substance – constant composition l 3 Methods of Separating Mixtures 1. Distillation – based on temperature each part changes from liquid to gas 2. Filtration – based on size of parts 3. Chromatography – based on parts in 2 different phases l