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General Chemistry. CHM 101. Dr. John Tyrell Office: Dobo 227 Telephone: 962-7299(campus); 793-3361(home) Email: tyrellj@uncw.edu http://people.uncw.edu/tyrellj/ Office Hours : W 9:45- 10:45 a.m. and by appointment. Drop ins welcome. Grading Policy:.
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General Chemistry CHM 101
Dr. John Tyrell Office: Dobo 227 • Telephone: 962-7299(campus); 793-3361(home) Email: tyrellj@uncw.edu • http://people.uncw.edu/tyrellj/ • Office Hours: W 9:45- 10:45 a.m. and by appointment. Drop ins welcome
Grading Policy: • Your grade in this course is based on your performance on the following items: • Hourly exams (there will be three of them): 50%Final exam: 20%Laboratory work: 15%Quizzes: 15% • Labs start today • (need lab manual & safety goggles)
Attendance & Homework • Attendance is expected, but not officially monitored for grading purposes. • Homework problems are assigned, but not collected. • Actively working on the homework problems allows you to test whether you understand the material and serves as a review guide for the exams.
Keys to Success • Come to class • Mind as well as body • Study three times: • Before the lecture • After the lecture • Before the test • Actively do problems. (keep a notebook) • Cooperation leads to graduation • It’s like a marathon – keep up a steady pace throughout
Let’s get started • Chemistry is the study of matter
The Study of Chemistry The Molecular Perspective of Chemistry • Matter is the physical material of the universe. • Matter is made up of relatively few elements. • On the microscopic level, matter consists of atoms and molecules. • Atoms combine to form molecules. • As we see, molecules may consist of the same type of atoms or different types of atoms.
The Study of Chemistry The Molecular Perspective of Chemistry • In these models, we use red to represent oxygen, white to represent hydrogen, and gray to represent carbon.
Classification of Matter States of Matter • Matter can be a gas, a liquid, or a solid. • These are the three states of matter. • Gases have no fixed shape or volume. • Gases can be compressed to form liquids. • Liquids have no shape, but they do have a volume. • Solids are rigid and have a definite shape and volume.
Classification of Matter Pure Substances and Mixtures • Atoms consist only of one type of element. • Molecules can consist of more than one type of element. • Molecules can have only one type of atom (an element). • Molecules can have more than one type of atom (a compound). • If more than one compound are found together, then the substance is a mixture.
Classification of Matter Pure Substances and Mixtures
Classification of Matter Pure Substances and Mixtures • If matter is not uniform throughout, then it is a heterogeneous mixture. • If matter is uniform throughout, it is homogeneous. • If homogeneous matter can be separated by physical means, then the matter is a mixture. • If homogeneous matter cannot be separated by physical means, then the matter is a pure substance. • If a pure substance can be decomposed into something else, then the substance is a compound.
Classification of Matter Pure Substances and Mixtures If a pure substance cannot be decomposed into something else, then the substance is an element.
Classification of Matter Compounds • Most elements interact to form compounds. • The proportions of elements in compounds are the same irrespective of how the compound was formed. • Law of Constant Composition (or Law of Definite Proportions): • The composition of a pure compound is always the same. • Therefore, if water is decomposed, then there will always be twice as much hydrogen gas formed as oxygen gas.