Atoms: the Building Blocks of Matter

Name: ______Page #: ______

ATOMS: SOME ELECTRIFYING one INFORMATION!

In this investigation, you will detect the tiny particles that not only serve as the building blocks of matter, but also hold the key to understanding electricity. Objective When you have completed this investigation, you should be able to analyze the characteristics of subatomic particles in order to determine how the flow of electrons produces an electric current. Activity 1 (Drill): Do You Know the Atom?

1. Discuss with your neighbor what you think an atom looks like. Draw your prediction below. Label any parts you can.

Prediction

2. How do you think atoms are related to electricity? (You actually already know.) Electrical energy is when electrons travel from atom to atom.

Activity 2: Pre-Reading 3. Preview the article, “The Atom,” paying specific attention to the use of text features. List 2 text features you see. Bold print diagram Title Parentheses Caption Blocked paragraphs

4. Review the bold-faced terms from the article. Circle any of the terms with which you are familiar. Vocabulary Definition a. the electrically neutral particles found in the nucleus of _c_ atom the atom b. the center of the atoms where the protons and neutrons are _f__ subatomic particles located c. the building blocks of all matter __b_ nucleus d. the area surrounding the nucleus occupied by the __g_ protons electrons of the atom e. the negatively charged particles circling the nucleus of _a_ neutrons the atom f. the smaller particles within an atom __e_ electrons g. the positively charged particle found in the nucleus of the _d_ electron cloud atom

Activity 3: Reading 5. Read the article, “The Atom.” 6. Match each term with its correct definition. Can you state the definition in your own words? Activity 4: Post Reading 7. Complete the graphic organizer below. Use the vocabulary from Activities 2 and 3.

MATTER

______ATOM______

Nucleus _electron cloud ______SUBATOMIC PARTICLES

(+) __ proton ( ) ___neutron (-) __electron ______

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8. Complete Figure 1, “Structure of the Atom”, by drawing two electrons, two protons, and two neutrons in the appropriate places. Use the symbols found in the key for each subatomic particle.

Figure 1 HELIUM ATOM Structure of the Atom

9. Label the electron cloud and the nucleus on “Structure of the Atom” diagram.

Activity 5: Analysis

10. Why is the electron the most likely subatomic particle to be lost or gained by an atom? Think about the size, location, and movement of electrons as opposed to protons or neutrons.

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11. Electric current is the result of what event within the atoms of a substance?

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The Atom

You see and touch hundreds of things everyday. Although they differ in many ways from one to another, they all share one important quality: they are all forms of matter. You already know that matter is anything that has mass and volume. But, have you ever wondered exactly what makes up matter? Atoms are the answer. That’s right. Atoms are the building blocks of all matter

Atoms are incredibly small. For example, it takes millions of atoms just to make the period at the end of this sentence. Since they are so small, scientists have not been able to observe them directly. Indirect evidence has led scientists to better understand the structure of an atom.

Based on the evidence gained from experiments, scientists believe that the atom actually has even smaller components known as subatomic particles. The three main subatomic particles are protons, neutrons, and electrons. All pure substances, such as gold, aluminum, or oxygen, are different from each other because their atoms contain different combinations of these three subatomic particles. These subatomic particles have specific locations, masses, and charges within the atom itself.

Protons and neutrons are located within the nucleus, or center Figure 2 of the atom (See Figure 2, The Nucleus). The positively charged The Nucleus particles found in the nucleus are called protons. Neutrons are the electrically neutral particles found in the nucleus. They have no charge. Almost all of the mass of the atom is found in the nucleus since protons and neutrons are much larger than electrons (They have about 2,000 times the mass of electrons.).

Whirling around the outside of the nucleus are electrons. Electrons have a negative charge. The exact location of an electron cannot be known. The area surrounding the nucleus occupied by the electrons is known as the electron cloud. Electrons are not as tightly bound to the atom as the protons and neutrons, so sometimes electrons move from atom to atom. It is this movement of electrons that has provided scientists with indirect evidence of the structure of the atom. Movement of electrons within some forms of matter can produce electricity. Electricity is used to power a variety of objects such as toasters, light bulbs, video games, and computers. Electricity has provided scientists with further evidence that subatomic particles exist within the atoms of matter.

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