Introduction to Chemistry

Chapter 1

Chemistry◦ The study of matter and changes it undergoes

Organic Chemistry◦ Carbon containing chemicals◦ Pharmaceuticals (drugs), plastics

Inorganic Chemistry◦ Matter with no Carbon◦ Minerals, metals and non-metals

Branches of Chemistry

Physical Chemistry◦ Behavior and change of matter and energy

(chemistry and physics combined)◦ Reaction Rates, reaction mechanisms (how fast

reactions take place and how to speed them up) Analytical Chemistry

◦ Composition of substance◦ Food nutrients, quality control, FDA

Biochemistry◦ Processes of living organisms◦ Metabolism, fermentation

Branches of Chemistry

The scientific method is an organized set of investigation procedures.

• 6 common steps1. State the problem2. Gather information3. Forming a hypothesis4. Testing the hypothesis5. Analyzing the data6. Drawing a conclusion

Scientific Method

1.State the Problem(Questions)2.Make Observation – do research

Visual Observations Existing Knowledge

3.Create a Hypothesis Tentative explanation, a testable statement or

prediction DOES NOT need to be a question

Scientific Method (Step 1,2,3)

4.Experiments Set of controlled observations Tests one variable at a time

Independent Variable- Plan to change Dependent Variable- Value changes in

response to independent variable Control Group- Standard for comparison Experimental Group – Where one changes the

independent variable.

Scientific Method (Step 4)

5.Data: Graphs, Tables, Lists, etc.Collect data

◦ Qualitative Data- describes a property w/out measurements, uses senses (ex. Color)

◦ Quantitative data – data collected using measurements (ex. Volume)

6.Conclusion Judgment based on information; Responds to purpose;

Analysis of results

Scientific Method (Step 5,6)

◦ Explanation supported by many, many experiments can be modified, lead to new conclusions

◦ Examples of Theories:

Scientific Theory

◦ No exceptions to laws, in any experiment

◦ Example of Laws:

 Scientific Law

Law of Conservation of Mass

Total amount of matter in the universe remains constant

Matter can’t be created nor destroyed Total amount b/4 reaction= total amount

after reaction Ex. Balancing equations

PbI demo

Law of Conservation of Energy Energy can’t be created nor destroyed Total amount remains constant Can transform into different types of energyEx. Match: potential chemical energy into

heat, light, sound, kinetic

Scientific Research◦ Pure Research: seeks for knowledge itself◦ Applied Research:To solve specific problem

(disease research) Chance discoveries

◦ Botox

Research

Anything that has mass and takes up space. Examples of matter:

Examples of non-matter:

Matter

a. Inertia

Resistance to change in motion or resistance to change in direction or rate

b. Mass

Amount of matter in an objectMeasure of the inertiaDoes NOT change from place to place

Measure with a balance

c. Weight

Measure of the force of gravity between 2 objects

Weight= mass X gravityChanges with locationMeasure with scale

2. Energy

Property possessed by matter, ability to do work

We are interested in the energy changes that take place

Types of Energy Potential- energy due to the objects

position, also stored energy (ex. Battery- chemical potential energy)

Kinetic- energy of motion Radiant- energy that goes in all directions

(light, x-rays, UV), transferred by electromagnetic waves

Other- heat, sound, nuclear, electric

Visual, verbal, and/or mathematical explanations of how things occur.

Where have you seen models before?

Models

Lab Equipment

Lab Equipment