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nyenohwin nyenohwin
wrote...
11 years ago
THE ONE WITH THE MOST SIMILARITIES AND DIFFERENCES WILL GET THE BEST ANSWER!
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ilikepie1234 Author
wrote...
11 years ago
The law of constant composition states that the ratio by mass of the elements in a chemical compound is always the same, regardless of the source of the compound. The law of constant composition can be used to distinguish between compounds and mixtures of elements: Compounds have a constant composition; mixtures do not. Water is always 88.8% O and 11.2% H by weight regardless of its source. Brass is an example of a mixture of two elements: copper and zinc. It can contain as little as 10%, or as much as 45%, zinc.

Another difference between compounds and mixtures of elements is the ease with which the elements can be separated. Mixtures, such as the atmosphere, contain two or more substances that are relatively easy to separate. The individual components of a mixture can be physically separated from each other.

Chemical compounds are very different from mixtures: The elements in a chemical compound can only be separated by destroying the compound. Some of the differences between chemical compounds and mixtures of elements are illustrated by the following example using raisin bran and "Crispix.".

Raisin bran has the following characteristic properties of a mixture.

The cereal does not have a constant composition; the ratio of raisins to bran flakes changes from sample to sample.
It is easy to physically separate the two "elements," to pick out the raisins, for example, and eat them separately.
Crispix has some of the characteristic properties of a compound.

The ratio of rice flakes to corn flakes is constant; it is 1:1 in every sample.
There is no way to separate the "elements" without breaking the bonds that hold them together.
wrote...
11 years ago Edited: 11 years ago, bio_man
mixtures
1) elements and compounds just mix together to form a mixture
    and no new compound is formed.
2)A mixture has a variable composition .
3)A mixture shows the properties of constituent substances
4)The constiuents can be seperated easily byphysical method.
5)They are generally heterogeneous i.e their composition   
    different points .
6)During the formation of mixture , no energy changes takes
   place .

    COMPOUNDS
1)Elements react to form a new compound
2)The composition of each new compound is fixed
3)The new substance has totally  different properties
4)The constituents can be seperated by chemical or                     
   electrochemical reactions.
5)They are always homogeneous, i.e.they have same composition throughout.
6)During the formation of compound the energy is either
   released oeabsorbed.

NOTE:- 1-4 of mixtures is related to 1-4 of compounds or 1-4 of mixtures r opposite of that of compound(1-4) .
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