Chapter 2,part A Chemical Principles
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings B.E Pruitt & Jane J. Stein Chapter 2, part A Chemical Principles
Chemistry Chemistry is the study of interactions between atoms and molecules. The atom is the smallest unit of matter that enters into chemical reactions. Atoms interact to form molecules
Chemistry • Chemistry is the study of interactions between atoms and molecules. • The atom is the smallest unit of matter that enters into chemical reactions. • Atoms interact to form molecules
The Study of Atoms Atoms are composed of Electrons:negatively charged particles Protons:positively charged particles Neutrons:uncharged particles
Atoms are composed of • Electrons: negatively charged particles • Protons: positively charged particles • Neutrons: uncharged particles The Study of Atoms
The Study of Atoms Protons and neutrons are in the nucleus. Electrons move around the nucleus. Electron shells Proton (p*) Nucleus Neutron(n) Electron(e)- Figure 2.1
• Protons and neutrons are in the nucleus. • Electrons move around the nucleus. The Study of Atoms Figure 2.1
Chemical Elements Each chemical element has a different number of protons. Isotopes of an element are atoms with different numbers of neutrons.Isotopes of oxygen are: O 0
• Each chemical element has a different number of protons. • Isotopes of an element are atoms with different numbers of neutrons. Isotopes of oxygen are: Chemical Elements 16 8O 17 8O 18 8O