To the first analytical group of cations by the acid-base classification belong such cations as:

Which reaction is used by Pharmacopoeia for identification of sodium-ions?

The chemist-analyst carries out the qualitative systematic analysis of the mixture of the first analytical group cations. Which cation is detected in the beginning of investigation by specific reaction?

Na⁺-ions colour the flame of the burner in:

Which cations are in the solution if the gas with a strong smell is liberated when heating with alkali?

When carrying out the reaction of sodium-ions with potassium hexahydroxostibiate (V) in neutral medium the precipitate is formed. Specify the colour of the precipitate:

K⁺-ions colour the flame of the burner in:

Choose the reagent for deleting NH₄⁺-ions before the К⁺-cations detection:

The dry residue obtained after evaporation of the solution to be analysed colours the colourless flame of the burner in a yellow colour, but when examining through a blue glass in a violet one. Which cations are present in the dry residue?

Choose the reagent for the K⁺-cations detection: