Ch 3: Praxis Biology: Science Principles - Numbers

About This Chapter

Use our video lessons and self-assessment quizzes to learn about systems of scientific notation and measurement. These lessons on numbers will aid you in preparing for the Praxis Biology test.

Praxis Biology: Science Principles - Numbers - Chapter Summary

This chapter's lessons cover numbers and how they are used for scientific measurements. The instructor will explain topics including the metric system, scientific notation and the pH scale. You will learn about the international system of units, called SI units, and explore concepts such as the difference between precision and accuracy. By the end of these lessons, you should be ready for questions on the Praxis Biology test that cover the following topics:

  • Units and conversion in the metric system
  • Dimensional analysis
  • Linear vs. logarithmic scale
  • Scientific notation and significant figures
  • Calculating a solution's pH or pOH

By showing you how numbers are used in scientific measurement, these concise videos will help you prepare for the exam. Many of the lessons use examples to explain the concepts covered, and you can test what you've learned by completing short quizzes at the end of each lesson. Links to the video lesson are provided, so it's easy to go back and review items again.

Praxis Biology: Science Principles - Numbers Chapter Objectives

In many states, teachers must pass the Praxis II exam in the subjects they wish to teach. The Praxis II Biology - Content Knowledge test consists of 150 multiple-choice questions. The test can be given on paper or on computer, and you will be allotted two hours to complete it. It is divided into six sections. The material covered in this chapter's lessons on numbers are in section I, Basic Principles of Science. This section has 12 questions, which comprise 8% of the test's total.

6 Lessons in Chapter 3: Praxis Biology: Science Principles - Numbers
Test your knowledge with a 30-question chapter practice test
The Metric System: Units and Conversion

1. The Metric System: Units and Conversion

Just like you and your friend communicate using the same language, scientists all over the world need to use the same language when reporting the measurements they make. This language is called the metric system. In this lesson we will cover the metric units for length, mass, volume, density and temperature, and also discuss how to convert among them.

Elements of the SI: Base & Derived Units

2. Elements of the SI: Base & Derived Units

Discover what we mean by SI units. Then explore SI units further by learning about all the base units, and several examples of the derived units that make up the system.

Unit Conversion and Dimensional Analysis

3. Unit Conversion and Dimensional Analysis

How is solving a chemistry problem like playing dominoes? Watch this lesson to find out how you can use your domino skills to solve almost any chemistry problem.

Significant Figures and Scientific Notation

4. Significant Figures and Scientific Notation

Are 7.5 grams and 7.50 grams the same? How do scientists represent very large and very small quantities? Find out the answers to these questions in this video.

Logarithmic Scale: Definition & Overview

5. Logarithmic Scale: Definition & Overview

A logarithmic scale is a useful way to represent information on a graph, especially when there are exponential changes in the magnitude of the numbers. Learn more, look at several examples and take a quiz to test your knowledge.

The pH Scale: Calculating the pH of a Solution

6. The pH Scale: Calculating the pH of a Solution

Learn the history of the pH scale, how to describe it and why it is used by scientists. Discover how to calculate the pH of an acid or base solutions given either the hydroxide ion concentration or the hydronium ion concentration. Learn how to start with the pH and calculate the hydroxide and hydronium ion concentrations.

Chapter Practice Exam
Test your knowledge of this chapter with a 30 question practice chapter exam.
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Practice Final Exam
Test your knowledge of the entire course with a 50 question practice final exam.
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