In the gold foil experiment of Geiger and Marsden, that paved the way for Rutherford's model of an atom, `~ 1.00%` of the `alpha`-particles were found to deflect at angles `gt 50^(@)`. If one mole of `alpha`-particles were bombarded on the gold foil, compute the number of `alpha`-particles that would deflect at angles less than `50^(@)`.

Explanation

Total number of `alpha`-particles used for bombardment = 1 mole
1 mole `= 6.022 xx 10^(23)` particles.
Number of `alpha`-particles deflected at angles greater than
`50^(@)(gt 50^(@)) = 1%" (Given)"`
`therefore` Number of `alpha`-particles deflected at the angles less than
`50^(@) = 100 -1 = 99%`
`therefore` Actual number of `alpha`-particles deflected at the angles less than
`50^(@) = (99)/(100) xx 6.022 xx 10^(23)`
`=5.96 xx 10^(23)`