JEE Main · 2022 · 24 Jun 2022 · Shift 2 · Practical and Analytical Chemistry

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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?

(A) $Cu^{2 +}$ ✓ Correct
(B) $Sr^{2 +}$
(C) $Ba^{2 +}$
(D) $Ca^{2 +}$

Answer: (A)

Solution

Cu^{2 +}

gives a green flame with a blue centre in the flame test.

Sr^{2 +}

gives crimson red,

Ba^{2 +}

gives apple green (without blue centre), and

Ca^{2 +}

gives brick red.

JEE Main · 2022 · 24 Jun 2022 · Shift 2 · Single correct option

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