Pure Substance 同 Mixture分別

PURE SUBSTANCE VS MIXTURE:
Pure substance:
-Formed CHEMICALLY.
-CAN'T be broken down by any process
-Elements (e.g. O) and Compounds (e.g. H2O) are pure substances.

Mixture:
-Formed PHYSICALLY.
-CAN be broken down by physical process
-Any substances that are form physically (e.g. Air) are mixtures.


ELEMENTS VS COMPOUNDS:
Elements:
-An element is an substance that can't be broken into two or more simpler substances.
-Element is a small but significant presence of a feeling or abstract quality.
-Symbols on the periodic table are elements.
-Examples: Iron (Fe) Gold (Au) Hydrogen (H) Carbon (C) Oxygen (O) Helium (He), etc.

Compounds:
-Made up of two or more types of elements (e.g. water and carbon dioxide) that are
chemically combined in a set ratio.
-Cannot be broken down into two or more simpler substances by physical means, only by chemical means.
-Properties of compounds differ from those of their elements. For example, salt is made up of two elements: chlorine, which is poisonous; and sodium, which
reacts explosively with water.
-Examples: Carbon dioxide (CO2), water (H2O), Sodium Chloride (NaCl),
FeO (Iron oxide)

2013-09-15 17:05:44 補充：
PURE SUBSTANCE VS MIXTURE:
Pure substance:
-CAN'T be broken down by any *physical* process

PURE SUBSTANCE VS MIXTURE

A single substance that has nothing else mixed with it is a pure substance such as pure copper wire and chlorine.
A mixture consists of two or more pure substances which have not been chemically joined together such as soda water, wine and coins.
PURE SUBSTANCE+PURE SUBSTANCE=MIXTURE

ELEMENTS VS COMPOUNDS

Elements are substances which cannot be broken down into anything simpler by chemical methods, such as hydrogen and oxygen. There are 111 elements i the whole world, 80% are obtained from the Earth's resources, 20% are artificially made by scientists.
Compounds are substances composed of two or more elements chemically joined together.
ELEMENTS + ELEMENTS = COMPOUNDS

純物質VS混合物

一個單一的物質，沒有任何其他東西混合在一起的，是一個純粹的物質，如純銅線和氯氣。
混合物是由兩個或兩個以上的純物質沒有被化學結合在一起，如蘇打水，酒和硬幣。
純物質+純物質混合物

元素VS化合物

元素的物質，通過化學方法，如氫氣和氧氣不能被細分成更簡單的東西。我整個世界，80％是從地球資源有111個元素，20％是人為由科學家。
的化合物是化學反應結合而成的兩種或多種元素組成的物質。
元素+元素=化合物

mixture係混合物，多過一種substance混合就係mixture，例如紅豆，綠豆係兩種substance，混合後就成為紅綠豆mixture，element 同 compound同樣解釋。