In the flame test of a mixture of salts, a green flame with blue centre was observed. Which one of the following cations may be present?
- \(Cu^{2+}\)
- \(Sr^{2+}\)
- \(Ba^{2+}\)
- \(Ca^{2+}\)
The Correct Option is A
Solution and Explanation
Green flame with Blue centre is given by Cupric salts.
Crimson red - \(Sr^{2+ }\)
Brick red - \(Ca^{2+ }\)
Green - \(Ba^{2+ }\)
Hence, the correct option is (A): \(Cu^{2+}\)
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Concepts Used:
Sparingly Soluble Salts
A sparingly soluble salt is so-called because when it is dissolved into a solvent, only a very small amount of the salt goes into the solution, and most of it remains undissolved. The solution becomes saturated with that little amount of salt dissolved, and the salt immediately dissociates into its ions.
Quantitatively, a solute is sparingly soluble if 0.1g (or less than that) of the solute is dissolved in 100ml of the solvent.