Welcome to the World of Chemistry Pre-AP Ch. 1 SAVE PAPER AND INK!!! When you print out the notes on PowerPoint, print "Handouts" instead of "Slides" in the print setup. Also, turn off the backgrounds (Tools>Options>Print>UNcheck "Background Printing")!

It’s because he was a teacher!!!

The Language of Chemistry CHEMICAL ELEMENTS - pure substances that cannot be decomposed by ordinary means to other substances. Aluminum Bromine Sodium

The Language of Chemistry The elements, their names, and symbols are given on the PERIODIC TABLE How many elements are there?

The Periodic Table Dmitri Mendeleev (1834 - 1907)

Glenn Seaborg (1912-1999) Discovered 8 new elements. Only living person for whom an element was named.

Branches of Chemistry Many major areas of study for specialization Several career opportunities Also used in many other jobs

1. Organic Chemistry Organic is the study of matter that contains carbon Organic chemists study the structure, function, synthesis, and identity of carbon compounds Useful in petroleum industry, pharmaceuticals, polymers

2. Inorganic Chemistry Inorganic is the study of matter that does NOT contain carbon Inorganic chemists study the structure, function, synthesis, and identity of non-carbon compounds Polymers, Metallurgy

3. Biochemistry Biochemistry is the study of chemistry in living things Cross between biology and chemistry Pharmaceuticals and genetics

4. Physical Chemistry Physical chemistry is the physics of chemistry… the forces of matter Much of IPC is computational Develop theoretical ideas for new compounds

5. Analytical Chemistry Analytical chemistry is the study of high precision measurement Find composition and identity of chemicals Forensics, quality control, medical tests

Is This Your Version of the Scientific Method??

Or Do You Feel Like This When Doing Science?

Scientific Method State the problem clearly. Gather information. Form a hypothesis. Test the hypothesis. Evaluate the data to form a conclusion. If the conclusion is valid, then it becomes a theory. If the theory is found to be true over along period of time (usually 20+ years) with no counter examples, it may be considered a law. 6. Share the results.

Hypothesis Hypothesis: A tentative statement about the natural world leading to deductions that can be tested. If the deductions are verified, the hypothesis is corroborated. If false, the hypothesis must be abandoned or revised. Good Example: If a plant is given only 2 minutes of sunlight every two weeks, the plant will die. Bad example: I think plants need sunlight to grow.

2 Types of Data: 1. Qualitative data- information that describes color, odor, shape, or some other physical characteristic. Think of it as anything that relates to the 5 senses- how something looks, feels, sounds, tastes, or smells. Think DESCRIPTIONS!!! 2. Quantitative data- data that can be measured: temperature, pressure, volume, quantity of a chemical formed, or how much of a chemical was used up in a reaction. Think NUMBERS!!!

Gathering Data with Experiments An experiment is a set of controlled observations that test the hypothesis. All experiments must have: An independent variable- is a variable that you can manipulate ex: (holding the temperature of the water to 200F to dissolve sugar) A dependent variable- is the variable that you do not know the outcome. Ex: How long it will take to dissolve the sugar. A control is a standard of comparison- Using room temperature water to dissolve sugar.

Once the Experiments Have Been Performed Numerous Times, They Can Become: Fact: an observation that has been repeatedly confirmed and for all practical purposes is accepted as “true”. Law: A descriptive generalization about how some aspect of the natural world behaves under stated circumstances. Theory: A well-substantiated explanation of some aspect of the natural world that can incorporate facts, laws, inferences, and tested hypothesis.

Graphs

shows how many of something Bar Graph shows how many of something are in each category

shows how a whole is broken into parts displayed as a PERCENTAGE! Pie Graph shows how a whole is broken into parts displayed as a PERCENTAGE! Percentage of Weekly Income

shows continuous change Line Graph shows continuous change Stock Price over Time

Elements of a “good” line graph axes labeled, with units use the available space title neat Hopefully, students will realize this data makes no sense. As temperature increase – the volume of a gas increases.

Graphs Line Graph Used to show trends or continuous change Bar Graph Used to display information collected by counting Pie Graph Used to show how some fixed quantity is broken down into parts GRAPHS Each graph is used for a specific reason.

Line Graph A B C D How does the mass of a penny change with age? Mass (g) Mass (g) Age (Year of Penny) Age (Year of Penny) C D LINE GRAPH Interpolate – estimate a value between data points on graph. Extrapolate – estimate a value beyond collected data points. Either before or after. **We have less confidence in data extrapolated than interpolated. In graph A: all pennies have the same mass (a reasonable hypothesis) - WRONG Graph B: older pennies have more mass (this may be due to the fact the pick up mass as they get dirty) - WRONG Graph C: older pennies have less mass (this may be caused by pennies wearing out in circulation) – WRONG Graph D: correct; pennies before 1982 were made of solid copper, and pennies after 1982 were made of a zinc core and a thin copper coating Mass (g) Mass (g) Age (Year of Penny) Age (Year of Penny)

Bar Graph Chemistry Grades Descriptive title Legend Number of Students Axis labeled (with units)

Pie Graph Note on graph of Earth’s crust that the majority of elements making up the Earth’s crust is oxygen and silicon. This is because they Earth is covered with sand (silicon dioxide (SiO2)). Aluminum composes a tremendous 7.5% of the Earth’s crust. Why recycle aluminum? It takes less energy (resources) to recycle aluminum than mine its ore and refine the ore to extract aluminum . Bottom line – it is cheaper to recycle the aluminum already mined from the Earth’s crust.

Safety Data Sheets (SDS) The OSHA ‘Material Safety Data Sheet’ (MSDS) will be called a ‘Safety Data Sheet’ (SDS) The MSDS has 8 non-mandatory sections The SDS would have 12 mandatory and 4 non-mandatory sections and is essentially the ANSI Z400.1-2004 format Sections 12-15 are not mandatory and cover Ecological, Disposal, Transport, and Regulatory information

Black border Transport GHS Labels Red border GHS ------ Black border Transport

GHS Labels (Global Health Symbols) Hazard Classes may have ‘Categories’

GHS Labels

Example of a Transportation and GHS label combined GHS Labels Example of a Transportation and GHS label combined