MCQ
Chalcogen group elements are:
- A$Se,$ $\mathrm{Tb}$ and $\mathrm{Pu}$.
- ✓$Se, Te$ and $Po.$
- C$\mathrm{S}, \mathrm{Te}$ and $\mathrm{Pm}$
- D$O, Ti$ and $Po.$
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$\frac{{dx}}{{dt}} = k\left[ P \right]{\left[ Q \right]^{0.5}}{\left[ R \right]^{0.5}}$
Which statement about the above equation is wrong?

At $t = 800\,s$, $[N_2O_5] = 1.45\,mol\,L^{-1}$
At $t = 1600\,s$, $[N_2O_5] = 0.88\,mol\,L^{-1}$