Difference between Qualitative and Quantative test?

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username3525694
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Can someone give me a very simple definition between the two and if possible a small example .

PS- what’s semi quantative ??
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QuentinM
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Quantitative is a test you take physical numerical measurements in. For example, a titration experiment would measure how many ml of an acid/base were added to neutralise the opposite chemical.

Qualitative tests involve making observations you can quantify. For example, if you are testing for starch with the starch iodide test, you can get either a positive or negative result-either purple staining or otherwise.

Semi-quantitative tests are usually qualitative tests, where a range of possible observations are possible-and whichever one you see gives you clues about a possible quantity. The best Biology example is the Benedict's test for sugars. Its a blue solution, which turns anything from Green, Yellow, Orange of Red depending on how much sugar there is. These are all rainbow colours-the closer to red it is, the more sugar there is in there. Its not a physical quantity most people would bother measuring (you could with a colorimeter) but gives you a good hint usually.

(I say usually because in that instance, different sugars also reduce to different extents, and hence unless the sample is made up of a specific sugar you know, its difficult to compare samples or accurately quantify)
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(Original post by QuentinM)
Quantitative is a test you take physical numerical measurements in. For example, a titration experiment would measure how many ml of an acid/base were added to neutralise the opposite chemical.

Qualitative tests involve making observations you can quantify. For example, if you are testing for starch with the starch iodide test, you can get either a positive or negative result-either purple staining or otherwise.

Semi-quantitative tests are usually qualitative tests, where a range of possible observations are possible-and whichever one you see gives you clues about a possible quantity. The best Biology example is the Benedict's test for sugars. Its a blue solution, which turns anything from Green, Yellow, Orange of Red depending on how much sugar there is. These are all rainbow colours-the closer to red it is, the more sugar there is in there. Its not a physical quantity most people would bother measuring (you could with a colorimeter) but gives you a good hint usually.

(I say usually because in that instance, different sugars also reduce to different extents, and hence unless the sample is made up of a specific sugar you know, its difficult to compare samples or accurately quantify)

Thank you soooooooooooooooooooo much
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Dysf(x)al
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(Original post by Aspiring•MEDIC)
Can someone give me a very simple definition between the two and if possible a small example .

PS- what’s semi quantative ??
I haven't come across semi-quantitative tests, but I can help you with the others.

Quantitative tests are about a quantity. If it's a number, it's quantitative. An example would be measuring your height.

Qualiative tests are about something you can't put a number on, such as an observation, colour or opinion. For example, your eye colour would be qualiative (unless you're nerdy enough to try to measure the wavelengths of light that it absorbs and reflects).
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