In 1909, Ernest Rutherford did a really important experiment called the Gold Foil Experiment. This experiment helped us learn some surprising things about atoms. Let’s break it down:

1. Nuclear Model of the Atom:

   • Most of the tiny particles called alpha particles (about 98%) went through the gold foil without any problems.
   • But, about 1 in 8000 alpha particles bounced off the foil at sharp angles.
   • This showed that there is a small, dense center in the atom, which we call the nucleus, and it has a positive charge.

2. Size of the Nucleus:

   • The nucleus is super tiny, about $10^{-15}$ meters wide.
   • When you compare that to the whole atom, which is about $10^{-10}$ meters, the nucleus is about 100,000 times smaller!

3. Conclusion:

   • Rutherford's experiment showed that atoms are mostly empty space, with a heavy center.
   • This changed how we think about atoms and helped create the modern understanding of the nuclear model of the atom.