Ch. 1.3 – Thinking Like a Scientist

How did alchemy lay the groundwork for chemistry?

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Nicolas Flamel, 1330-1418

The Alchymist, In Search of the Philosophers’ Stone

Alchemists developed the tools and techniques for working with chemicals.

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Alchemy

Alchemists developed processes for separating mixtures and purifying chemicals. They designed equipment that is still in use today including beakers, flasks, tongs, funnels, and the mortar and pestle.

Mortar and Pestle

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An Experimental Approach to Science

How did Antoine Lavoisier, “the Father of Modern Chemistry”, help to transform chemistry?

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Lavoisier helped to transform chemistry from a science of qualitative observation to the science of quantitative measurement that it is today.

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•Lavoisier designed a balance that could measure mass to the nearest 0.0005 gram.

•He also showed that oxygen is required for a material to burn.

•He discovered that, although matter may change its form or shape, its mass always remains the same.

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The Scientific Method

What are the steps in the scientific method?

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The scientific method is a logical, systematic approach to the solution of a scientific problem.

Steps in the scientific method include making observations, testing hypotheses, and developing theories.

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The Scientific Method

Making Observations

When you use your senses to obtain information, you make an observation.

Suppose you try to turn on a flashlight and it does not light. An observation can lead to a question: What’s wrong with the flashlight?

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The Scientific Method

Testing Hypotheses

A hypothesis is a proposed explanation for an observation.

You guess that the flashlight needs new batteries. You can test your hypothesis by putting new batteries in the flashlight. If the flashlight lights, you can be fairly certain that your hypothesis is true.

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The Scientific Method

An experiment is a procedure that is used to test a hypothesis. When you design experiments, you deal with variables, or factors that can change.

• The variable that you change during an experiment is the manipulated variable, or independent variable.

• The variable that is observed during the experiment is the responding variable, or dependent variable.

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The Scientific Method

Developing Theories

Once a hypothesis meets the test of repeated experimentation, it may become a theory.

• A theory is a well-tested explanation for a broad set of observations.

• A theory may need to be changed at some point in the future to explain new observations or experimental results.

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The Scientific Method

Scientific Laws

A scientific law is a concise statement that summarizes the results of many observations and experiments.

A scientific law doesn’t try to explain the relationship it describes. That explanation requires a theory.

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Steps in the Scientific Method

The Scientific Method1.3

Collaboration and Communication

Collaboration and Communication

What role do collaboration and communication play in science?

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Collaboration and Communication

No matter how talented the players on a team, one player cannot ensure victory for the team. Individuals must collaborate, or work together, for the good of the team.

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

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Collaboration and Communication

Collaboration

Scientists choose to collaborate for different reasons.

• Some research problems are so complex that no one person could have all of the knowledge, skills, and resources to solve the problem.

• Scientists might conduct research for an industry in exchange for equipment and the time to do the research.

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Collaboration and Communication

Collaboration isn’t always a smooth process. You will work on a team in the laboratory. You may face some challenges. But you can also experience the benefits of collaboration.

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Collaboration and Communication

Communication

Scientists communicate face to face, by e-mail, by phone, and at international conferences.

Scientists publish their results in scientific journals. Articles are published only after being reviewed by experts in the author’s field.

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1.3 Section Quiz.

1. Lavoisier is credited with transforming chemistry from a science of observation to a science of

a. speculation.

b. measurement.

c. hypotheses.

d. theories.

1.3 Section Quiz.

2. A hypothesis is

a. information obtained from an experiment.

b. a proposed explanation for observations.

c. a concise statement that summarizes the results of many of experiments.

d. a thoroughly tested explaination for a broad set of observations.

1.3 Section Quiz.

3. Why are articles in scientific journals the most reliable source of information about new scientific discoveries?

a. The articles are reviewed by experts in the author's field.

b. Any article that is submitted is published.

c. Everyone has access to the information.

d. The articles are short and easy to read.

END OF SHOW