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Chemistry Lesson 2. What is an Atom?. Do-Now. What is the definition of an element?. Atoms. Think about the word “Atom” What do you already know about the Atom? List it on the back of your “do-now” worksheet. Atoms.
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Chemistry Lesson 2 What is an Atom?
Do-Now • What is the definition of an element?
Atoms • Think about the word “Atom” • What do you already know about the Atom? List it on the back of your “do-now” worksheet
Atoms • Now that you’ve listed some things you know about atoms, turn to the person next to you and share.
What is an Atom? • An Atom is the basic particle from which all elements are made. • Atoms are made up of smaller particles called protons, electrons, and neutrons
What is an Atom? • A proton has a positive charge (+) • A electron has a negative charge (-) • A neutron has neither a positive or negative charge. It is neutral.
What is an Atom? • In an atom, the number of protons is the same as the number of electrons. • The electrical charges balance, so the atom as a whole is neutral
Parts of an Atom • The two main parts of an atom are the nucleus and the electron cloud. • The nucleus is the very small center core of the atom. It contains protons and neutrons. • The electron cloud is a cloud of negative charge that surrounds the nucleus. It contains electrons.