Tuesday, December 13, 2011

Lewis Dot Diagrams

Here is some additional review material for Lewis Dot Diagrams.  With break coming so soon, I know some review help will probably be in order for January, and now you're ready to go!

Electron Dot Structures (aka Lewis Dot Diagrams)

Also, here are some good images:

Atoms and Compounds:


Polyatomic Ions:
Nitrate and Carbonate (remember: each one has a negative charge (CO3 -2 and NO3 -1)...it's just not written in)

Sulfate:    Ammonium:



Friday, December 9, 2011

Review Material for Next Test

Reminder: Your next test is coming at the beginning of next week!  It will cover the material we have  talked about from Chapter 13.  Here are the test dates:

1st hour: Monday 12/12
5th hour: Tuesday 12/13

Here are the topics we have covered, and a few resources to help you study!
  • Electron Orbital Diagrams
  • Electron Configuration
  • History of atom models and scientists’ contributions to our understanding of the atom: Democritus to Schrodinger
  • The 3 Rules for filling orbital diagrams
  • Orbital shapes
  • Noble Gas Configuration
  • Quantum Numbers
  • Creation of electromagnetic radiation (light and “invisible light”)
  • Vocabulary: quantum, atomic orbitals, energy levels, quantum mechanical model, sublevels, atomic emission spectra
Resources:
http://www.chemguide.co.uk/atoms/properties/atomorbs.html (shapes of orbitals, electron orbital diagrams)
http://www.brazosport.edu/sites/CurrentStudents/Faculty/JudyChu/Tutorials/elecconf3.htm (writing electron configuration, filling electron orbital diagrams, the 3 rules of filling)
http://chemistry.bd.psu.edu/jircitano/periodic4.html (atomic emission spectra of elements)

    Sunday, November 13, 2011

    Answer Key: ChemQuest! Packet

    Here is the answer key for the packet on types of chemical reactions.  It would be useful to go over the equations for predicting products and reactants because that's a skill you'll need for the test!

    Chemquest! Chemical Reactions

    Test Dates:
    1st Hour--Thursday 11/17
    5th Hour: Friday 11/18

    Monday, November 7, 2011

    Types of Reactions

    This week we are dealing with types of reactions.  There are five main categories:

    1. Combustion
    2. Synthesis
    3. Decomposition
    4. Single Replacement
    5. Double Replacement

    It's really fairly easy to categorize the reactions we see in class into one of these 5 categories, but if you want to see a good animation to help you get up to speed, I suggest watching this short You Tube video:

    Five Major Chemical Reactions

    What we do with these categories is what you will most likely find difficult.  We're going to take what we know about the categories and use it to predict what products will form in a reaction!  You all are starting to think like real chemists now...before chemists even think about mixing any chemicals together, they always use what they know about the reactants to predict what they will be making.  A mistake at this step could be really dangerous!

    Tuesday, November 1, 2011

    Chapter 8

    Up next: Chapter 8

    We're going to be looking at: chemical equations, balancing, types of chemical reactions, and predicting the products of reactions.  The best way to do this is by PRACTICE!  Some of you are good at balancing equations, but if you need extra help, try this activity:

    Balancing Equations Tutorial: ChemBalancer

    Again, nothing for a grade or that I can see, but it might be useful to you!

    Wednesday, October 19, 2011

    Upcoming Test!

    Just a reminder that in the middle of next week, you will have your 2nd test of the year!  It's going to cover all of the naming we have done in this unit, but don't fret:  you get to use your periodic tables.

    Your periodic table is like a cheat sheet for this test.  All of the following will be useful:
    • Charges at the top of the representative element families
    • Knowing what section contains the transition metals (hint: that tells you that you need to use roman numerals!), and where to find metals/nonmetals (so you know if you have an ionic compound...metal-nonmetal...or a molecular compound...nonmetal-nonmetal)
    • The big list of polyatomic ions on the back side (know how to use them!)
    • The small box of prefixes at the bottom of the front side (hint: only use them for molecular compounds!  nonmetal-nonmetal)

    Monday, October 17, 2011

    Chemistry Nomenclature

    A little confused about naming?  Here's some additional help:

    Naming Binary Ionic Compounds (see part I)
    Naming Binary Compounds with Polyatomic Ions
    Naming Binary Molecular Compounds (see the 1st part)

    Even though it may not be exciting, the best way to study this is to do a lot of practice problems.  This is why you have the 4 page packet of problems...by the end you should be a master of naming!


    Wednesday, October 5, 2011

    Review: Atoms and the Periodic Table

    Here is some review for the parts of the atom, parts of the periodic table, and the information that you can find on the periodic table.  Keep in mind, however, that your notes will have a few more important things you need to know about (such as the important chemists and their discoveries, what metals and nonmetals do in terms of electrons, and ions vs. isotopes).  This is just a supplement to the material you've already gotten in class :)

    Extra Review: Atoms and the Periodic Table

    Thursday, September 29, 2011

    "The First Family Can't Swim"

    If nothing else, we learned one thing in class today: the first family can't swim.  Here are videos of each element being put in water...notice any pattern?

    Lithium (Li)
    Sodium (Na)
    Potassium (K) 
    Rubidium (Rb)
    Cesium (Cs)
    Francium (Fr)...bomb

    Tuesday, September 27, 2011

    Ch. 5 Atoms, Introduction

    So you heard Mr. Stewart's atom analogy, where you pictured the room as an atom.  Here's another good one:  If a golfball was an atom's nucleus, then the whole atom would be the size of a half-mile wide sphere!  Pretty crazy, huh?

    The idea of an atom as a mostly empty sphere with a tiny nucleus was proposed by one of the most famous chemists in history: Ernest Rutherford.  Interesting fact:  he was a research assistant for J.J. Thompson, the man that proposed atoms were like plum pudding (or jello salad).  Nothing like proving your boss wrong...

    Here's a good video showing a re-make of Rutherford's Gold Foil Experiment

    If you aren't much of an artist and would like to see some more information about the different atomic theories and models throughout history this table has a nice break down of the discoveries and changes throughout history, and where we are today.

    Any of you stuck on writing chemical symbols with their atomic number (# of protons), atomic mass (protons +neutrons), and charge (difference between protons and electrons)?  Maybe this visual will help:

    While this is an example for sodium (Na), the numbers should appear in the same places for all elements.

    Thursday, September 22, 2011

    Safety: Hydrochloric Acid

    As with any chemical, it's important to know what the safety concerns are.  This week we have been using HCl (hydrochloric acid), and I want to provide you with a bit more information about handling it safely.  For most of you this is already understood, but I strongly suggest reading what is below.  While some of this information is more relevant to you than some of the other details, too much information is never a bad thing when it comes to safety.  As always, let us know if you suspect you spilled or got something on you!

    Common Routes of Hydrochloric Acid Exposure

    • Inhalation. The most common way for hydrochloric acid to enter the body is through the respiratory
      system. Signs and symptoms of hydrochloric acid inhalation can include:
      • Coughing
      • Choking
      • Burning of the throat
    • Contact with the Skin. Hydrochloric acid can irritate the skin and cause chemical burns ranging from mild to severe depending on the concentration of the hydrochloric acid solution. Concentrated vapor or solution may cause the victim to experience pain, redness of the skin, and blisters. Signs displayed by skin exposed to liquefied hydrochloric acid can include frostbite, tissue death, or severe burns with deep ulcerations.
    • Contact with the Eyes. Hydrochloric acid, even with short-term exposure, can irritate the eyes and cause burning, swelling, tearing of the eyes, blurred vision, photophobia, sloughing of the surface cells of the eye, and may cause blindness.
    • Ingestion. Immediate burning in the mouth and throat occur when hydrochloric acid is swallowed. Ingestion of concentrated solution can cause severe pain in the mouth, chest and abdomen, nausea and vomiting.

    First Aid Management

    Prompt action is essential if there is a hydrochloric acid spill or leak. If a hydrochloric acid spill or leak occurs, take the following actions:
    • Breathing
      If hydrogen chloride is inhaled, move the person to fresh air at once. If breathing stops, perform artificial respiration. Keep the affected person warm and resting. Seek medical attention immediately.
    • Eye Exposure
      Wash eyes immediately with large amounts of water for at least 15 minutes, lifting the upper and lower lids. Seek medical attention immediately. Contacts should not be worn when working with hydrogen chloride/ hydrochloric acid.
    • Skin Exposure
      Skin contaminated with hydrogen chloride/ hydrochloric acid should be flushed with water for at least 15 minutes. Do not rub or wash skin. If strong concentrations of gas or solution penetrate clothing, remove clothing and flush the skin with water. Seek medical attention immediately.
    More Information: Hydrochloric Acid Exposure

    Wednesday, September 21, 2011

    Study Tool! Chemical Equations

    Here is a terrific link that breaks down chemical equations and the Law of Conservation of Mass:

    Chemical Equation Review

    When going to this link, you have the ability to watch and listen to video, as well as complete practice problems (click on the tab above the video).  I would pay particular attention to the following (you can click on these titles in the left side bar):
    • Identifying the reactants and products
    • Identifying the coefficients
    • Distinguishing subscripts from coefficients
    • Identifying liquids, solids, gases, and aqueous solutions
    • Overview for the Law of Conservation of Mass

    Monday, September 19, 2011

    Study Tools! Chapter 2

    Here are some good online quizzes to help you study some of the material from Chapter 2:

    Elements & Compounds Self-Quiz

    Element, Compound, or Mixture? Self-Quiz

    Don't forget that your test is coming up! (Friday for 5th hour, and Monday for 1st hour)

    Using the Site, First Lab

    Hi, all!
    Just a note about the Calendar feature on the class site.  When looking at it, there are events for multiple subjects...you should only concern yourself with those labelled "Chem" (GS=geophysical science).  Also, if you ever see a number after "Chem," the number refers to the hour.

    Hopefully none of you are too intimidated about going into the lab tomorrow.  It's going to be a busy class period, but one where you finally get to start mixing things together and conducting experiments!  As always, if you ever have questions, don't be afraid to ask.