Chapter 1

What is Chemistry

Chemistry is the study of the composition of matter and the changes matter

undergoes

What is matter?

Anything that has a mass and takes up

space

Chemistry affects all aspects of life and

most natural events

Areas of Study

There are 5 traditional areas of study

1. Organic Chemistry – study of all chemicals containing carbon

2. Inorganic Chemistry – study of chemicals that, in general, do not contain carbon

3. Biochemistry – study of processes that take place in organisms

4. Analytical Chemistry – focuses on the composition of matter

5. Physical Chemistry – area that deals with the mechanism, the rate, and the energy transfer that occurs when matter undergoes a change

Pure and Applied Chemistry

Pure chemistry is the pursuit of chemical knowledge for its own sake

Applied chemistry is research that is directed toward a practical goal or application

Pure research can lead directly to an application, but an application can exist before research is done to explain how it works

Ex. People were using aspirin for pain relief long before researchers knew how it worked.

This lead to a system of applied science called technology

The means by which a society provides its members with those things needed and desired

Why Study Chemistry

Explaining the natural world – chemistry can help you satisfy your natural desire to

understand how things work

Preparing for a career – chemists, firefighters, and photographers are just a few jobs that require a knowledge of

chemistry

Being an informed citizen – you will need to make choices that will influence the

development of technology

How do we do this?

Section 2Chemistry Far and Wide

Materials

Chemists design materials to fit specific needs

A Swiss scientist used the burr as a model for the invention of Velcro

There are 2 different ways to look at the world

Macroscopic – those things seen with the unaided eye

Microscopic – those things seen with the help of a microscope

Energy

Chemists play an essential role in finding ways to conserve energy, produce energy, and store energy

Conservation – Insulation is one of the easiest ways to conserve heat

Production – the burning of fossil fuels is the main form of energy production

Since fossil fuel supply is running low so scientists are designing alternative energy supplies

Storage – energy can easily be stored in batteries

Rechargeable batteries reduce waste

Medicine and biotechnology

Chemistry supplies the medicines, materials, and technology that doctors use to treat their patients

Medicines – there are over 2000 prescription drugs

Materials – chemists have made many products that can replace body parts

Biotechnology applies science to the production of biological parts

Bacteria are inserted with a human gene which produces insulin

Agriculture

Chemists help to develop more productive crops and safer, more effective ways to protect crops

Productivity – chemists help solve problems with poor soil quality, lack of water, weeds, plant diseases, and pests

Crop Protection – Insects produce chemicals that fight insect pests

The Universe and Environment

Chemists help to identify pollutants and prevent pollution

Identify – Lead was commonly used in paint and gasoline. Lead has been identified as a pollutant

Prevention – blood tests, regulation of home sales, public awareness campaigns

To study the universe, chemists gather

data from afar and analyze matter that is brought back to earth

Section 3Thinking Like a Scientist

Alchemy

The word chemistry comes from alchemy

Alchemists developed processes for separating mixtures and purifying chemicals

They also designed beakers, flasks, tongs, and various other equipment

French Scientist Antonine-Larent Lavoisier transformed chemistry from a science of observation to a science of measurement

He is responsible for determining that oxygen is required for materials to burn

The Scientific Method

The scientific method is a logical,

systematic approach to the solution

of a scientific problems

Steps:

Making Observations – often leads to a question

Hypothesis – proposing an explanation for the problem

The Scientific Method

Steps:

Experiment– procedure with variables used to test the hypothesis

Manipulated Variable – the one that is deliberately changed

Responding Variable – the one that changes in response to the manipulated variable

Developing Theories – once a hypothesis has been tested many times with the same results it will become a theory

Theories can never be proven correct

Scientific Law– a concise statement that summarizes the results of many observations

Collaboration and Communication

When scientists collaborate and communicate, they increase the likelihood of a successful outcome

Collaboration is often used because no one scientist has all the knowledge, skills, and resources to solve a problem

Scientists communicate their findings primarily through scientific journals

Why is the internet not the best source for scientific information?

Section 4Problem Solving in Chemistry

Solving Numeric Problems

Effective problem solving always involves developing a plan and then implementing that plan

There are 3 steps for solving a numeric word problem

1. Analyze

Identify the “known” and “unknown”

Identify units

Plan how to solve problem

Solving Numeric Problems

2. Calculate

Calculations are the easiest part

You might need to convert measurements or rearrange an equation

3. Evaluate

Does your answer make sense?

Did you include correct units and # of significant figures

Sample Problem 1.1

Solving Conceptual Problems

Not all word problems require calculations

Some problems require you to apply concepts

Steps to a conceptual problem

1. Analyze

2. Solve

Conceptual problem 1.1