The compounds that produce $\mathrm{CO}_2$ with aqueous $\mathrm{NaHCO}_3$ solution are:

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The metal ion whose electronic configuration is not affected by the nature of the ligand and which gives a violet colour in non-luminous flame under hot condition in borax bead test is

Consider ' n ' is the number of lone pair of electrons present in the equatorial position of the most stable structure of $\mathrm{ClF}_3$. The ions from the following with ' n ' number of unpaired electrons are

A. $\mathrm{V}^{3+}$

B. $\mathrm{Ti}^{3+}$

C. $\mathrm{Cu}^{2+}$

D. $\mathrm{Ni}^{2+}$

E. $\mathrm{Ti}^{2+}$

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The correct order of stability of following carbocations is :