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본 문서의 분량 : 57 페이지 |
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materials science is based on the study of matter
composition of materials structure of materials
properties of matter and changes that occur in matter or under e. g
interaction with electromagnetic radiation.
to study matter some characterization methods, instruments, and analysis tools are required.
description of materials properties describing a change of composition iron changes to rust change to carbon dioxide and water change to carbon dioxide decomposition to a mixture of gases chemical properties corrosion of metals fe o2 fe2o3 burning of alcohol alcohol o2 co2 h2o burning of carbon c o2 co2 explosion of nitroglycerine n2o3 h2o description of materials properties physical properties color odor solubility hardness electrical conductivity
mass volume density temperature boiling point melting point
describing a feature
copper is red.vinegar smells.
table salt dissolves in water.diamond is a hard.
metal conducts electricity.
nickel has a mass of 5 g. alcohol has a volume of 100 ml
water density is 1g/ml.
temperature of air is 22 oc.water boils at 100 oc.
ice melts at 0 oc.
qualitative quantitative classifying matter according to its state solid liquid gas gas-chaotic motions of molecules, liquid-week interaction between molecules solid:
crystalline-atoms, ions or molecules are regular ordered in the space forming a crystal lattice.
consequence: sharp melting point at specific temperature
physical properties, like mechanical, optical and electrical properties could be anisotropic along the crystallographic axis, graphite.
amorphous-e.g.glass, not organized crystal structure, physical properties are isotropic (identical)
states of matter solid state
atoms, ions or molecules are close packed to each other in fixed locations, cannot move around each other giving solid, fixed volume and rigid shape.
ice, diamond, iron are examples long-ranged repeated order well ordered geometric arrangement of atoms salt no order
classifying matter according to its composition
made up of atoms of only a single type, carbon, oxygen made up of 2 or more elements no fixed composition compound element element chemical reaction: fixed proportion h2o combination of chemical symbols: (이하 생략)
