0
What branch of chemistry carries out tests to identify an unknown substance?
Wiki User
∙ 11y ago
Analytical chemistry is concerned with investigation of the quantitative and/or qualitative characteristics of a given sample. For instance, an analytical chemist may qualitatively determine what the various polycyclic aromatic hydrocarbons in a tar sample are, and may also quantitatively analyze the concentrations of each species in the sample.
Wiki User
∙ 11y ago
Add your answer:
Earn +20 pts
Name several properties of matter that help you identify an unknown substance?
Every thing
What is meant by a characteristic property of a substance?
Since characteristic properties for a given substance never change, they can be used to identify unknown matter.
What is meant by a mixed melting-point determination?
"Mixed melting point determination" is a term used in chemistry. Organic substances have a fixed temperature at which they liquify. If a chemist wants to determine the nature of an unknown substance, he can determine it by these means. If the unknown substance does not melt at the usual temperature, it can be said to be impure. If the chemist has two unknown substances and wants to determine what they are, he may mix equal parts of each and start the liquification process. If the combination melts at the usual temperature, the chemist can say that both are the same. If the chemist wants to determine the nature of an unknown substance, he may mix a fixed amount of a known substance with a fixed amount of an unknown substance, it can be estimated, what the unknown substance is.
How you might use Rf values to identify an unknown substance?
Although Rf values technically remain constant if the following are held constant: * solvent system * adsorbent * thickness of the adsorbent * amount of material spotted * temperature They are generally not used to identify an unknown substance specifically, since these factors are sometimes difficult to control. Most generally, during a chromatography experiment an unknown sample can be compared directly to a known sample simultaneously, i.e. they will have similar Rf values.
What is a general term for any isotope of any element?
The word substance is used in chemistry to describe elements or compounds. It is used because when dealing with an unknown substance, it is important to not assign either name to it.
Knowing the solubility of an unknown substance in water can help to identify what it is.?
Knowing the solubility of an unknown substance in water can help you calculate its molarity. It is however important to get its weight first.
What happens when you mix francium with a substance?
The chemistry of francium is practically unknown today.
Name several properties of matter that help you identify an unknown substance?
Every thing
What is meant by a characteristic property of a substance?
Since characteristic properties for a given substance never change, they can be used to identify unknown matter.
Why Do You Think Scientists Can Use The Basic Properties Of Matter To Help Identify An Unknown Substance?
Because if a substance can't be known then it has to prove its mass and volume
Where can quantitative analysis be used in chemistry?
Forensics. QA is used to find what sort of chemical or compound is present in an unknown substance.
What can be used to identify an unknown substance?
Just about any property that can be observed or measured can help you reduce the number of options.
Why is it important to identify an unknown substance?
Because the substance could potentially be extremely toxic or harmful. You must never use an unknown substance in experiments without identifying it first, many tests can be undertaken to determine the cation and anion. These tests include the flame test, solubility tests, precipitate reaction tests and conductivity tests. These do vary depending on the unknown substance.
What can be used to help identify an unknown substance?
Just about any property that can be observed or measured can help you reduce the number of options.
What is meant by a mixed melting-point determination?
"Mixed melting point determination" is a term used in chemistry. Organic substances have a fixed temperature at which they liquify. If a chemist wants to determine the nature of an unknown substance, he can determine it by these means. If the unknown substance does not melt at the usual temperature, it can be said to be impure. If the chemist has two unknown substances and wants to determine what they are, he may mix equal parts of each and start the liquification process. If the combination melts at the usual temperature, the chemist can say that both are the same. If the chemist wants to determine the nature of an unknown substance, he may mix a fixed amount of a known substance with a fixed amount of an unknown substance, it can be estimated, what the unknown substance is.
If you had an unknown substance and were asked to identify it would you use the intensive or extensive properties of the substance?
Intensive properties are independent from the mass of an object: density, hardness, melting point.
How do forensic scientists analyze unknown powders?
Forensic labs are often called in to identify unknown powders, liquids and pills that may be illicit drugs. There are basically two categories of forensic tests used to analyze drugs and other unknown substances: Presumptive tests (such as color tests) give only an indication of which type of substance is present -- but they can't specifically identify the substance. Confirmatory tests (such as gas chromatography/mass spectrometry) are more specific and can determine the precise identity of the substance.
