Oxygen in oxides has oxidation number -2.
<span>Al⁺³₂O⁻²₃
+3*2 -2*3=0</span>
It is important to compare the positive and negative test results with those of known compounds as positive results indicate the presence of that known compound and negative results indicate the absence of that compound which is used for reference.
<h3>What is qualitative analysis?</h3>
Qualitative chemical analysis is a method to determine the chemical composition of a sample.
There are two types of qualitative analysis:
- Organic Qualitative analysis: It helps in determining the chemical bonds and functional groups in a sample
- Inorganic qualitative analysis: It helps in determining the ions in the given sample
There are seven ways to analyze a sample qualitatively, which are
A reference compound is always used to which results are compared.
A Positive result indicates that the reference compound is present in the sample whereas a negative result indicates that the reference compound is absent in the given sample.
Learn more about qualitative analysis:
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