In the Gold foil experiment of Geiger and Marsden, that paved the way for Rutherford’s model of an atom, ~ 1.00% of the α-particles were found to deflect at angles > 50º. If one mole of α-particles were bombarded on the gold foil, compute the number of α-particles that would deflect at angles less than 500.
ScienceClass 9CBSEAnswered 27 Mar 2026
Answer
Soln:
Total number of α particles used for bombardment = 1 mole 1 mole=6.022x1023 particles
number of α particles deflected at angles greater than 50°(>50°)= 1% Number of α particles deflected at angles greater than 50° =100-1= 99%
Actual number of α particles deflected at angles less than 50°= 99
100
× 6.022 × 1023
=5.96× 1023
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