Electronic Structure and Chemical Bonding Finding the minimum uncertainty in a position or velocity measurement An atom of helium has a radius
r_(He)=31.pm
and an average speed in the gas phase at
25\deg C
of
787.(m)/(s)
. Suppose the speed of a helium atom at
25\deg C
has been measured to within
0.10%
. Calculate the smallest be known to be located with certainty. Write your answer as a multiple of
r_(He)
and round it to 2 significant figures. For example, if the smallest bo radius of an atom of helium, you would enter "42.r He " as your answer.
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