Monday, October 8 •  Lecture 8 (Last Week) –  ALEKS Assessments –  Specific Heat (2.5) –  Energy & NutriFon (2.6) –  Experiment #2: Calorimetry •  Lecture 9 (Today) –  Calorimetry (Experiment #2) –  Elements and Symbols (3.1) –  The Periodic Table (3.2) Exam 1 & DRS Accommodations
Today Exams to DRS Office Exam 1 If you plan to request DRS accommodaFons, submit your form to me by Monday 10/15 •  in person or in my mailbox (1st floor of Bagley, Box #71) ALEKS: Open Pie Time
•  You will be in open pie 'me whenever you complete •  an objec've and •  the objec've comple'on assessment before the objec've deadline. •  During open pie 'me you can work on any part of the course •  ALEKS won’t give you specific tasks to focus on •  You have 3 opFons: 1.  work ahead 2.  work on old (uncompleted) objecFves 3.  take a break EvaporaFon vs. Boiling A liquid such as water can slowly turn to a gas (evapora'on) or rapidly turn to a gas (boiling) At T < Tbp At T = Tbp Some molecules at the surface of the liquid have enough KE to enter gas phase, even at temperatures below the boiling point. Molecules in the bulk liquid have enough KE that they begin to vaporize within the liquid, not just at the surface. VaporizaFon occurs at the surface of the liquid only. Experiment #2: Calorimetry Calorimetry involves measuring the heat of chemical reacFons Important features of a Calorimeter InsulaFon Known (measured) amount of water Thermometer Chemical reacFon or other process SFrring Filling Out “Hazard Diamonds” Fire •  Will this material start fires? •  Will this material make an exisFng fire worse? Health •  Danger to people if consumed, touched, etc. Special warnings •  Does this material pose special risks? Hazard Diamond for H2O ReacFvity •  Is this material unstable? •  Does it react with water or other common chemicals? Boiling Chips (or Boiling Stones) Boiling chips are unreacFve solids used when liquids are heated in laboratories •  There are many types of boiling chips •  They may be white, black, etc. •  Their rough surface gives bubbles a place to form (bubble formaFon is called nucleaFon) If boiling chips are not used, the liquid may become superheated •  Superheated liquids can suddenly boil violently and are dangerous •  If boiling chips are added to hot liquid they can cause rapid boiling (dangerous) If you are going to heat a liquid: 1.  Add a boiling chip BEFORE you begin heaFng 2.  If you FORGET to add a boiling chip, cauFously cool the liquid to room temperature, THEN add the boiling chip Reminder: Lab 1 Postlab reports are due at the beginning of Lab 2 Chapter 3: Atoms and Elements Elements
Elements are pure substances from which all other
things are built.
gold
carbon
aluminum
9
Sources of Some Element Names
Some elements are named for planets, mythological
figures, minerals, colors, scientists, and places.
Symbols of Elements
A symbol
§  represents the name of an element.
§  consists of 1 or 2 letters.
§  starts with a capital letter.
Examples:
1-Letter Symbols
C carbon
N nitrogen
F
fluorine
O oxygen
2-Letter Symbols
Co
cobalt
Ca
calcium
Al
aluminum
Mg
magnesium
Symbols of Common Elements
Symbols of some common elements:
S, sulfur
Au, gold
Al, aluminum
Ag, silver
The Periodic Table of Elements 03_T05.JPG Reading the Periodic Table “A” groups 1 “B” groups (transiFon metals) 1A 13 14 15 16 17 18 3A 4A 5A 6A 7A 8A 3 4 5 6 7 8 9 10 11 12 1B 2B 3B 4B 5B 6B 7B 8B 9B 10B These elements are also part of the transiFon metal block Periodic Trends