What is the value of effective atomic number of cobalt in $$\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_6\right]^{3+}$$ complex if $$\mathrm{Co}(\mathrm{Z}=27)$$ ?

For the reaction, $$3 \mathrm{~I}+\mathrm{S}_2 \mathrm{O}_8^{2-} \rightarrow \mathrm{I}_3^{-}+2 \mathrm{SO}_4^{2-}$$, at a particular time $$\mathrm{t}, \frac{\mathrm{d}\left[\mathrm{SO}_4^{2-}\right]}{\mathrm{dt}}$$ is $$2.2 \times 10^{-2} \mathrm{~mol} \mathrm{~dm}^{-3} \mathrm{~s}^{-1}$$. What is the value of $$-\frac{\mathrm{d}\left[\mathrm{I}^{-}\right]}{\mathrm{dt}}$$ ?

What is the total number of Bravais lattices present for different crystal systems?

Identify compound $$\mathrm{Y}$$ in the following reaction. $$\mathrm{C}_2 \mathrm{H}_5 \mathrm{Cl}+\mathrm{Y} \stackrel{\Delta}{\longrightarrow} \mathrm{C}_2 \mathrm{H}_5 \mathrm{CN}$$