MCQ
If the radius of first orbit of $H$ atom is $a_0$, the de-Broglie wavelength of an electron in the third orbit is
- A$4\pi {a_0}$
- B$8\pi {a_0}$
- ✓$6\pi {a_0}$
- D$2\pi {a_0}$
$r = {a_0} \times {(3)^2} = 9{a_0}$
$mvr = \frac{{nh}}{{2\pi }};$
$mv = \frac{{nh}}{{2\pi r}} = \frac{{3h}}{{2\pi \times 9{a_0}}} = \frac{h}{{6\pi \,{a_0}}}$
$\lambda = \frac{h}{{mv}} = \frac{h}{h} \times 6\pi {a_0} = 6\pi {a_0}$
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$CS_2 + 3O_2 \,\,\to \,\, 2SO_2 + CO_2$