Monthly Archives: October 2016

Test on Friday, Oct. 14

Sorry class, the test is tomorrow. You are more prepared than you think. Titration will not be on the test. From unit 1, focus on empirical formula, % composition limiting reactants, and % yield. From Unit 2, focus on how electrolytes dissociate in water, identifying if a substance is soluble or insoluble from solubility tables, neutralization reactions, precipitate reactions, redox reactions (and for all three types writing the molecular reaction and the net ionic reaction.) and molarity. ON the test you will have a question similar to your lab report calculations, a question like #28 on the homework packet, and you will have to explain how to create a solution of certain molarity from mass and dilution, just like we did in class the other day. When reviewing HW packet #1, focus on ?s # 3,5,9,10,11,12,14,16 and 17. From packet #2, focus on ?s #1,2,5,7-11, 14-16,19 and 28.

Before Class Oct. 12 Intro to Energy

Before class on Oct. 12,

  • Please watch the three videos below.;
  • Complete these notes;
  • Make a comment
  • In addition, read this short text from Brown and LeMay, Chemistry: the Central Science, and answer the thinking questions on your notes. Everything we do is connected in one way or another with energy. Not only our modern society but life itself depends on energy for its existence. The issues surrounding energy – its sources, production, distribution, and consumption – pervade conversations in science, politics, and economics, and relate to environmental concerns and public policy.

    Think: List one current event topics that you might understand better if you had a better understanding of energy.

    With the exception of energy from the Sun, most of the energy used in our daily lives comes from chemical reactions. The combustion of gasoline, the production of electricity from coal, the heating of homes by natural gas, and the use of batteries to power electronic devices are all examples of how chemistry is used to produce energy. Even solar cells rely on chemistry to produce the silicon and other materials that convert solar energy directly to electricity. In addition, chemical reactions provide the energy that sustains living systems. Plants use solar energy to carry out photosynthesis, allowing them to grow. The plants in turn provide food from which we humans derive the energy needed to move, maintain body temperature, and carry out all other bodily functions.

    List three ways we use energy in our daily lives:

    Think: It is evident that the topic of energy is intimately related to chemistry.  What exactly is energy, though, and what principles are involved in its production, consumption, and transformation from one form to another? Write down your thoughts about this question now.

     

Sept. 28/29 : Naming Ionic Compounds and Reviewing Vocabulary

If you were absent from class today, or just need a review, today our guiding question was:

How do we know what to name compounds, and we do we give them a name that is different from the elements that make them up?  For example, “Why is  AlCl3 called aluminum chloride?”

Here is a picture of the Table of Contents from today:

file-oct-01-3-18-23-pm

By the end of the lesson today, you will have learned how to:

  • Write the symbol and charge of an ion after being given the number of protons and electrons;
  • Write the formula of an ionic compound after being given the ions or the name;
  • Write the name of an ionic compound after being given the formula;
  • Define an ionic bond and explain how it holds ions together in a molecule.