Presentation on theme: " Unit 1 Loose Ends and Test Review Unit 1 Loose Ends and Test Review You are getting a classwork grade for how DILIGENTLY you work on the worksheet. Turn."— Presentation transcript:
Unit 1 Loose Ends and Test Review Unit 1 Loose Ends and Test Review You are getting a classwork grade for how DILIGENTLY you work on the worksheet. Turn in WHAT YOU FINISH by the end of class. If you want to take it home, for study purposes, see me AFTER 3 rd period.
Qualitative and Quantitative Data Qualitative (think quality) These are observations usually. It’s blue. It’s hot. It’s cool. It’s smells like rotten eggs. Remember to look for qualitative date when you do your lab experiments. Quantitative (think quantity or amount) These are the numbers you measure. 5.0 g of baking soda. 2L of diet Coke. 4.5 moles of CO 2. Remember to record quantitative data in your lab notebook when you do experiments too.
Errors We will discuss error primarily in our labs. Always include a discussion of any errors that happened in your experiment in your “Analysis of Data” section of your lab report. What kind of errors can you have in your labs? Random Systemic
Errors http://www.budapesthotels.com/sitepic/error_button.png http://images.intomobile.com/wp-content/uploads/2009/06/easy-button.jpg Random errors are mistakes. You can reduce or eliminate random errors. These usually come from being unprepared (not reading the lab prior to doing it), rushing to get done, and careless errors (like forgetting to do a step). Systemic errors are errors that are present in your system. You can’t do anything about these. If your data is precise, but not accurate this might indicate that you had systemic error. Easy Button Error Button
Sig Figs 50 just means that your measurement is somewhere between 49 and 51. 50.0 means that your measurement is somewhere between 49.9 and 50.1 50.00 means that your measurement is somewhere between 49.99 and 50.01 50.000 means that your measurement is somewhere between 49.999 and 50.001 The more sig figs in your measurement, the more confidence you have that it’s “exactly” 50 mL or 50 g.
Density http://www.stevespanglerscience.com/img/cache/bcb9b8db117ee64376aedaf7af3595ca/sevenlayer-2-51908.jpg Higher density layers on the bottom and lower density layers on the top. Is oil more or less dense than water?
Density is WHY Ice Floats http://www.dharma.org/ims/images/pi_ice_on_pond.jpg Ice is actually kind of strange, because water is a very unique compound. Most substances are more dense as a solid than they are as a liquid. Ice is an exception to this rule. If ice didn’t float, all the fish in this lake would die during the winter.
Measure your Kinetic Energy = Take Your Temperature! http://www.avogadro.co.uk/miscellany/t-and-p/thermometers.gif Kelvin temperature was defined to be a measure of the kinetic energy of the sample of matter. 0K is ABSOLUTE zero. A sample of matter at 300K has twice as much kinetic energy as a sample of matter at 150K. Temperature is directly proportional to kinetic energy. You must remember how to convert from °C to K and vice versa. It WILL be on the SOL. You need a formula!
Organic Flavor This year, we will have an Organic Chemistry and Biochemistry “flavor” from time to time. Organic = any compound which contains carbon. Biochem = study of organic compounds which appear in living things.
Organic Products ≠ Organic Chemistry Many people prefer organic products for lots of reasons. People think they are eating healthier and not putting “chemicals” into their body by using organic products. However, scientific evidence (so far) proves that there is little difference in organic produce in terms of taste, safety and nutritional value compared to “non-organic” produce.
Organic Compounds All organic compounds contain C. Originally organic meant “comes from nature.” H owever, not all organic compounds come from nature or living things today. Some are created by scientists in a lab.
Aspirin Aspirin occurs naturally in willow tree bark. It is an organic compound. Hippocrates (father of modern medicine) was known to make a powder of willow bark and leaves to cure headaches and fevers as early as 400 BC. Aspirin was first isolated chemically in Germany in 1897 at Bayer, a chemical company. Aspirin is quite easy to make in the lab (we do it in AP Chem). Many pharmaceutical products are very difficult to make, however.
Hydrocarbons The simplest organic compounds are called hydrocarbons. These compounds ONLY contain C and H. Hydrocarbons are also called “fossil fuels” (because they come from decomposed living things) and “petrochemicals” (because they are found in petroleum). Petroleum is a mixture of hydrocarbons found in geologic formations beneath the Earth’s surface.
HC = Hydrocarbons Petroleum (also known as crude oil) is separated by distillation. Oil and gasoline, and a lot of other comounds, are in the mixture known as “petroleum.” In distillation, you boil a mixture of hydrocarbons. Since each hydrocarbon has a unique boiling point, they can be separated from each other in this way. (Test alert!) The simplest HC is methane. Methane’s formula is CH 4. Learn this!
HC = Hydrocarbons A saturated hydrocarbon contains the maximum amount of hydrogen. Saturated means it cannot take any more than it already has. An unsaturated hydrocarbon does NOT contain the maximum amount of hydrogen. It can take more. It also means that there are double or triple bonds in the compound.
Polymers Large molecule composed of repeating units of simple molecules (called monomers). Mono = one Poly = many Think about Legos blocks. Each block is a monomer. When you hook a bunch of blocks together, you get a large chain (the polymer). There are two types of polymers (more on this in a later unit). Natural Synthetic (not natural or man-made)
Polymers Natural Polymers Proteins (monomer = amino acids) Starch and Cellulose (monomer = sugar molecules) DNA and RNA (monomer = purine and pyrimidine bases) Synthetic Polymers Plastics polyethylene (PE) also known as polythene polyvinylchloride (PVC) polystyrene also known as Styrofoam Sodium polyacrylate (the absorbent polymer in Huggies diapers) Fibers (nylon, rayon, polyester) Kevlar (produced in Richmond, VA) Teflon (polytetrafluoroethylene)
The End What is next? Unit 2: Chapter 4, 5, 6, 25.