Question

place the atomic particles in order from the first one discovered to the last one discovered. 1. proton 2. electron 3. neutron

Explanation:

Electrons were discovered first (J.J. Thomson in 1897), protons next (E. Goldstein in 1886, but concept -ually more developed later), and neutrons last (James Chadwick in 1932).

Answer:

1. electron
2. proton
3. neutron