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Mixture or substance?

  • #1
567
3
A mixture is defined as 2 substances that are arbitirarily combined. They are either homogenous or heterogenous.

A substance is defined as being homogenous and has definite, fixed composition that is NOT arbitrary.

On some classwork we did, this following was stated as being true:

wood is a.....answer: mixture

sodium chloride is a...... answer: mixture

I disagree; wood is a substance because it has a fixed composition by definition. And since sodium chloride is a compound, it is not a mixture either; it is a substance.
the choices for classification on the worksheet was "mixture" or "substance".
I am confused...please help.

thanx
 

Answers and Replies

  • #2
Pengwuino
Gold Member
4,989
15
Wood is not a substance. There is no chemical compound that can be called "wood". A wood is a large mixture of various chemicals and compounds.
 
  • #3
567
3
thank you!!!!

How about sodium chloride then? it is a substance?
 
  • #4
Pengwuino
Gold Member
4,989
15
Yes.. its ordinary table salt.
 
  • #5
138
0
Think of it this way, a substance can not be physicly broken down into somthing else.

A mixture can be physicly seperated (Like filtering a mixture)
 
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