MCQ
General outer electronic configuration of d-block elements is:
- A(n - 1)d1-10 ns3
- B(n + 1)d1-10 ns 0-2
- C(n - 1)d1-10 ns0-2
- D(n - 1)d0 ns0-2
Explanation:
d-block elements are elements of group 3 to 12 in the centre of the periodic table. So, general outer electronic configuration = (n - 1)d1-10 ns0-2.
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$CH_3OH(l)+ \frac{3}{2} O_2 (g) $$\rightarrow CO_2 (g)+ 2H_2O(l)$
At $298\, K$ standard Gibb's energies of formation for $CH_3OH(l),H_2O(l)$ and $CO_2 (g)$ are $-166.2,-237.2$ and $-394.4\, kJ\,mol^{-1}$ respectively. If standard enthalpy of combustion of methonal is $-726 \,kJ\, mol^{-1},$ efficiency of the fuel cell will be .......... $\%$.
