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• Chemistry is the science that investigates and explains the relationship between structure and properties of matter.

Chemistry and Matter: Basic ConceptsChemistry and Matter: Basic Concepts

• Matter is anything that takes up space and has mass.

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• Mass is the measure of the amount of matter that an object contains or its inertia.

• The properties of matter describe the characteristics and behavior of matter, including the changes that matter undergoes.

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Chemistry and Matter: Basic ConceptsChemistry and Matter: Basic Concepts

Mass vs. weight

Chemistry and Matter: Additional ConceptsChemistry and Matter: Additional Concepts

Branches of ChemistryBranch Area of Emphasis Examples

Organic chemistry

most carbon-containing chemicals pharmaceuticals, plastics

Inorganic chemistry

in general, matter that does not contain carbon

minerals, metals and nonmetals, semi-

conductorsPhysical

chemistrythe behavior and changes of matter

and the related energy changesreaction rates,

reaction mechanismsAnalytical chemistry

components and composition of substances

food nutrients, quality control

Biochemistry matter and processes of living organisms

metabolism, fermentation

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Scientific Methods

• Qualitative data vs. quantitative data

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Chemistry and Matter: Basic ConceptsChemistry and Matter: Basic Concepts

•A quantitative observation is one that uses measurement.

• A qualitative observation is one that can be made without measurement.

Scientific Methods• The variable that is

changed in an experiment is called the independent variable.

• The variable that you watch to see how it changes as a result of your changes to the independent variable is called the dependent variable.

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Chemistry and Matter: Additional ConceptsChemistry and Matter: Additional Concepts

Scientific Research

• Pure research is done to gain knowledge for the sake of knowledge itself.

• Applied research is undertaken to solve a specific problem.

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Chemistry and Matter: Additional ConceptsChemistry and Matter: Additional Concepts

Scientific Methods

• A typical scientific method includes:

• making observations,

• forming a hypothesis, • performing an experiment,

• and arriving at a conclusion.

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Chemistry and Matter: Additional ConceptsChemistry and Matter: Additional Concepts

Scientific Methods

• Many experiments also include a control, which is a standard for comparison.

• A conclusion is a judgment based on the data obtained in the experiment.

• If data support a hypothesis, the hypothesis is tentatively affirmed. Hypotheses are never proven; they are always subject to additional research.

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Chemistry and Matter: Additional ConceptsChemistry and Matter: Additional Concepts

• A scientific model is a thinking device that helps you understand and explain macroscopic observations. Scientific models are built on experimentation.

Using Models in Chemistry Chapter 1

Chemistry and Matter: Basic ConceptsChemistry and Matter: Basic Concepts

Scientific Methods• Often, a scientist will begin with qualitative

data—information that describes color, odor, shape, or some other physical characteristic that relates to the five senses.

• Chemists also use numerical quantitative data.

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Chemistry and Matter: Additional ConceptsChemistry and Matter: Additional Concepts

• A hypothesis is a possible explanation for what has been observed.

• An experiment is a set of controlled observations that test a hypothesis.

Scientific Methods

• Over time, data from many experiments can be used to form a visual, verbal, and/or mathematical explanation—called a model—of the phenomenon being studied.

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Chemistry and Matter: Additional ConceptsChemistry and Matter: Additional Concepts

• A theory is an explanation that has been supported by many experiments.

• Theories are always subject to new experimental data and are modified to include new data.

Scientific Methods

• A scientific law describes a relationship in nature that is supported by many experiments and for which no exception has been found.

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Chemistry and Matter: Additional ConceptsChemistry and Matter: Additional Concepts

Additional Assessment Questions

Identify the dependent variable and the independent variable in the following experiments.

Question 1 Chapter 1

A student tests the ability of a given chemical to dissolve in water at three different temperatures.

independent variable: temperature; dependent variable: ability to dissolve in water

Answer 1a

Question 1a Chapter 1

Additional Assessment Questions

A farmer compares how his crops grow with and without phosphorous fertilizers.

independent variable: presence of phosphorous fertilizer; dependent variable: crop growth

Answer 1b

Question 1b Chapter 1

Additional Assessment Questions

Classify each kind of research as either pure or applied.

Question 2chapter 1

Additional Assessment Questions

A scientist studies plants in a rain forest in search of chemicals that might be used to treat AIDS.

applied

Answer 2a

Question 2a chapter 1

Additional Assessment Questions

A researcher studies the effects of hormones on the brain of a worm.

pure

Answer 2b

Question 2b chapter 1

Additional Assessment Questions

A researcher tries to develop cleaner burning fuels to help reduce air pollution.

applied

Answer 2c

Question 2c chapter 1

Additional Assessment Questions