Why is the bottom of a kettle blackened and top polished?

1 Answers  

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What is positive testing in relation to chemistry? For example, the sentence reads "Sample solutions are solutions known to contain one of each of the following ions, silver ion, Ag+(aq), barium ion, Ba2+(aq), and iron (III) ion, Fe3+(aq). Testing solutions are the solutions containing a polyatomic ion that can react with one of the metal ions to give a positive test." I am then asked to define what a "positive test" is. I am currently a student who is pretty new to chemistry, please try and make your answer as simply as possible. Thanks for the help.

2 Answers   UST,

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What is the effect of the flashes of lightning during a thunderstorm ?

2 Answers  

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What is meant by amalgam ?

2 Answers  

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What is Acids, Bases salts ?

2 Answers   Viva,

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How will you calculate how many moles of glucose present in 320 ml of 5.0 m of glucose solution?

0 Answers  

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What is protein - according to chemistry?

0 Answers  

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How many elements have been discovered on the Periodic Table?

10 Answers   ESRI,

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why in atomic mass electron is not include while proton and neutron include? although electron is a part of atom.

2 Answers  

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From which substance are the dues manufactured ?

1 Answers  

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What is General Properties of Acids ?

4 Answers   College School Exams Tests, TCS,

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can we Consider the Purity threshold and Purity angle in place of peak purity for the specificity test for method verification

0 Answers   Alkem Labs,

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