4、地球物质的化学组成 Rock and Minerals inearth Atomic Structure All natural and most synthetic substances on earth are made from the ninety naturally occurring chemical elements. An atom is the smallest particle into which an element can be divided while still retaining the chemical characteristics of that element (fig 3. 1). The nucleus, at the center of the atom, contains one or more particles with a positive electrical charge(protons Dif and usually some particles of similar mass that have no charge(neutrons Hf ) Circling the nucleus *k are the negatively charged electrons 环质 Environmental Geology
环境地质学 Environmental Geology 4、地球物质的化学组成 Rock and Minerals in earth Atomic Structure All natural and most synthetic substances on earth are made from the ninety naturally occurring chemical elements. An atom is the smallest particle into which an element can be divided while still retaining the chemical characteristics of that element (fig 3.1). The nucleus, at the center of the atom, contains one or more particles with a positive electrical charge (protons质子) and usually some particles of similar mass that have no charge (neutrons中子 ). Circling the nucleus核 are the negatively charged electrons
4、地球物质的化学组成 Rock and Minerals inearth Neutron charge 0 mass 1 Prc charge mass 1 Electron charge-1 ss very small 环质 Environmental Geology
环境地质学 Environmental Geology 4、地球物质的化学组成 Rock and Minerals in earth
4、地球物质的化学组成 Rock and Minerals inearth Elements and Isotopes 4 With the exception of the simplest hydrogen atoms, all nuclei contain neutrons and the number of neutrons is similar to or somewhat greater than the number of protons. The number of neutrons in atoms of one element is not always the same. The sum of the number of protons and the number of neutrons in a nucleus is the atom's atomic mass number. Atoms of a given element with different atomic mass numbers-in other words, with the same number of protons but different numbers of neutronsare distinct isotopes of that element. Some elements have only a single isotope, while others may have ten or more. (The 环质 Environmental Geology
环境地质学 Environmental Geology 4、地球物质的化学组成 Rock and Minerals in earth Elements and Isotopes 4. With the exception of the simplest hydrogen atoms, all nuclei contain neutrons, and the number of neutrons is similar to or somewhat greater than the number of protons. The number of neutrons in atoms of one element is not always the same. The sum of the number of protons and the number of neutrons in a nucleus is the atom's atomic mass number. Atoms of a given element with different atomic mass numbers—in other words, with the same number of protons but different numbers of neutrons—are distinct isotopes of that element. Some elements have only a single isotope, while others may have ten or more. (The
4、地球物质的化学组成 Rock and Minerals inearth Chemical Symbols 8. Each chemical element is denoted by a one-or two-letter symbol Many of these symbols make sense in terms of the English name for the element--o for oxygen, He for helium, si for silicon, and so on Other symbols reflect the fact that, in earlier centuries, scientists were generally versed in Latin or Greek: The symbols Fe for iron and Pb for lead for example, and derived from ferrum and plumbum, respectively, the latin names for these elements 环质 Environmental Geology
环境地质学 Environmental Geology 4、地球物质的化学组成 Rock and Minerals in earth Chemical Symbols 8. Each chemical element is denoted by a one-or two-letter symbol. Many of these symbols make sense in terms of the English name for the element--O for oxygen, He for helium, Si for silicon, and so on. Other symbols reflect the fact that, in earlier centuries, scientists were generally versed in Latin or Greek: The symbols Fe for iron and Pb for lead, for example, and derived from ferrum and plumbum, respectively, the Latin names for these elements
4、地球物质的化学组成 Rock and Minerals inearth Minerals defined 11. A mineral is naturally occurring, inorganic, solid element or compound with a definite chemical composition and a regular internal crystal structure. Naturally occurring, as distinguished from synthetic means that minerals do not include the thousands of chemical substances invented by humans. Inorganic means not produced solely by living organisms or by biological processes. That minerals must be solid means that the ice of a glacier is a mineral, but liquid water is not Chemically, minerals may consist either of one element-like diamonds, which are pure carbon--or they may be compounds of two or more elements. Some mineral compositions are very complex, consisting of ten elements or more. Minerals have a definite chemical composition or a compositional range within which they fall. The presence of certain elements in certain proportions is one of 环质 Environmental Geology
环境地质学 Environmental Geology 4、地球物质的化学组成 Rock and Minerals in earth Minerals Defined 11. A mineral is naturally occurring, inorganic, solid element or compound with a definite chemical composition and a regular internal crystal structure. Naturally occurring, as distinguished from synthetic, means that minerals do not include the thousands of chemical substances invented by humans. Inorganic means not produced solely by living organisms or by biological processes. That minerals must be solid means that the ice of a glacier is a mineral, but liquid water is not. Chemically, minerals may consist either of one element-like diamonds, which are pure carbon--or they may be compounds of two or more elements. Some mineral compositions are very complex, consisting of ten elements or more. Minerals have a definite chemical composition or a compositional range within which they fall. The presence of certain elements in certain proportions is one of
4、地球物质的化学组成 Rock and Minerals inearth Identifying characteristics of Minerals 12. The two fundamental characteristics of a mineral that together distinguish it from all other minerals are its chemical composition and its crystal structure. No two minerals are identical in both respects, though they may be the same in one. For example, diamond and graphite(the"lead"in a lead pencil) are chemical the same--both are made up pure carbon. Their physical properties, however, are vastly different because of the differences in their internal crystalline structures. In a diamond, each carbon atom is firmly bonded to every adjacent carbon atom in every direction. In graphiteA 33, the carbon atoms are bonded strongly in two dimensions into sheets, but the sheets are only weakly held together in the third 环质 Environmental Geology
环境地质学 Environmental Geology 4、地球物质的化学组成 Rock and Minerals in earth Identifying Characteristics of Minerals 12. The two fundamental characteristics of a mineral that together distinguish it from all other minerals are its chemical composition and its crystal structure. No two minerals are identical in both respects, though they may be the same in one. For example, diamond and graphite (the “lead” in a lead pencil) are chemical the same--both are made up pure carbon. Their physical properties, however, are vastly different because of the differences in their internal crystalline structures. In a diamond, each carbon atom is firmly bonded to every adjacent carbon atom in every direction. In graphite石墨, the carbon atoms are bonded strongly in two dimensions into sheets, but the sheets are only weakly held together in the third