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In statistical hypothesis testing, a two-sample test is a test performed on the data of two random samples, each independently obtained from a different given population. The purpose of the test is to determine whether the difference between these two populations is statistically significant .
A test method is a method for a test in science or engineering, such as a physical test, chemical test, or statistical test. It is a definitive procedure that produces a test result. [ 1 ] In order to ensure accurate and relevant test results, a test method should be "explicit, unambiguous, and experimentally feasible.", [ 2 ] as well as ...
The Carius halogen method measures halides quantitatively. [1] Chemical tests for cyanide test for the presence of cyanide, CN −; Copper sulfate tests for the presence of water; Flame tests test for metals; The Gilman test tests for the presence of a Grignard reagent; The Kjeldahl method quantitatively determines the presence of nitrogen
The closed testing principle allows the rejection of any one of these elementary hypotheses, say H i, if all possible intersection hypotheses involving H i can be rejected by using valid local level α tests; the adjusted p-value is the
In a qualitative test a sample is first reacted with a mixture of acetic acid and hydrogen iodide in a test tube. The ensuing reaction results in the cleavage of the ether or the ester into an alkyl iodide and respectively an alcohol or a carboxylic acid .
Analytical chemistry consists of classical, wet chemical methods and modern analytical techniques. [2] [3] Classical qualitative methods use separations such as precipitation, extraction, and distillation. Identification may be based on differences in color, odor, melting point, boiling point, solubility, radioactivity or reactivity.
The one-sample version serves a purpose similar to that of the one-sample Student's t-test. [2] For two matched samples, it is a paired difference test like the paired Student's t -test (also known as the " t -test for matched pairs" or " t -test for dependent samples").
In organic chemistry, the bromine test is a qualitative test for the presence of unsaturation (carbon-to-carbon double or triple bonds), phenols and anilines. An unknown sample is treated with a small amount of elemental bromine in an organic solvent, being as dichloromethane or carbon tetrachloride. Presence of unsaturation and/or phenol or ...