Warm-Up ? Elements Lesson Question Lesson Goals Explore Examine the Describe the . Explain how form. of an element. W 2K of an element. Words to Know Fill in this table as you work through the lesson. You may also use the glossary to help you. a substance that is made up of two or more elements electrons found in the outermost energy level of an atom that are used in bonding the number of protons in the nucleus of an atom a substance that is made up of only one type of atom © Edgenuity, Inc. 1 Warm-Up Elements Atoms Atoms are the part of matter, and cannot be separated into smaller parts by ordinary means. They are made up of: • a • An © Edgenuity, Inc. that contains protons and neutrons. that contains electrons. 2 Instruction Elements Slide 2 Elements An is a pure substance, which means it: • is made of only one type of • be broken down into a simpler form. • makes up all 4 . in the universe. Chemical Symbols of Elements • The symbols below represent different . • These symbol are all one, two, or three letters long. Hg Ti Carbon © Edgenuity, Inc. Titanium Iron Mercury 3 Instruction Elements Slide 4 Protons in an Element Elements are identified by their Atomic number of He: [2] . Atomic number of Ca: Atomic number of [20] Pt: [20] Electrons in an Element • Electrons occupy the . • Each electron occupies an state. • Electrons from the nucleus occupy a energy state. • The electron cloud is divided into • Each energy level can hold a certain number of • © Edgenuity, Inc. . . are usually found in the highest energy level. 4 Instruction Elements Slide 6 Elements on Earth REAL-WORLD CONNECTION A limited number of make up the Earth. Two or more elements may combine to form . • Table salt (NaCl) is a compound made up of sodium (Na) and chloride (Cl). • Water (H2O) is a compound made up of hydrogen (H) and oxygen (O). • A compound is a pure substance because it can be isolated. 9 Words to Know Fill in this table as you work through the lesson. You may also use the glossary to help you. an atom or group of atoms with either a positive or ion negative an atom that has the isotope a number of protons but number of neutrons than other atoms of the same element the number of protons and neutrons in the mass number nucleus of an atom © Edgenuity, Inc. 5 Instruction Elements Slide 9 Isotopes An has the number of protons but a number of neutrons than other atoms of the same element. • Some elements may have many isotopes. • Others only have a few. Names of Isotopes Isotopes are identified by their , the total number of protons and neutrons in the nucleus of an atom. Carbon-12 has 6 protons and © Edgenuity, Inc. neutrons. Carbon-14 has 6 protons and neutrons. 6 Instruction Elements Slide 12 Ions • The number of protons in an atom is to the number of electrons. • No overall • form when one or more electrons are lost or gained. • charge: an electron is lost • charge: an electron is gained Positive Ions • A positive ion is formed when one or more electrons are lost from the atom. • A sodium atom that one electron becomes an ion. • Since there is one more proton than electron, the ion is (Na+1). Sodium atom © Edgenuity, Inc. Sodium ion 7 Instruction Elements Slide 12 Negative Ions • A negative ion is formed when one or more electrons are gained by an atom. • A chlorine atom that one electron becomes an ion. • Since there is one more electron than proton, the ion is (Cl-1). © Edgenuity, Inc. 8 Summary ? Elements Lesson Question What are elements and how do they differ? Answer Slide 2 Review: Key Concept Elements: • are made up of only • are substances. • combine to form • make up . matter in the universe. • can be identified by chemical © Edgenuity, Inc. type of atom. and number. 9 Summary Elements Slide 2 Review: Key Concepts ISOTOPES AND IONS Isotopes have the number of protons but a number of neutrons than other atoms of the same element, and are identified by . • An example of an isotope is , which has 6 protons and 8 neutrons. Ions form when one or more electrons are • A loss of electrons results in a • A gain of electrons results in a © Edgenuity, Inc. or . ion. ion. 10 Summary Elements Use this space to write any questions or thoughts about this lesson. © Edgenuity, Inc. 11
