Question
The de-Broglie wavelength associated with a hydrogen molecule moving with a thermal velocity of $3 km/s$ will be ............ $\mathop A\limits^o $
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Answer
(b) $\lambda = \frac{h}{{m{v_{rms}}}}$
==>$\lambda = \frac{{6.6 \times {{10}^{ - 34}}}}{{2 \times 1.67 \times {{10}^{ - 27}} \times 3 \times {{10}^3}}} = 0.66\,{Å}$
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