Question

what could j. j. thomson conclude from his experiments?
○ atoms are mostly empty space.
○ most of the mass of the atom is concentrated in the center.
○ atoms must balance positive and negative particles.
○ atoms are indivisible.

Explanation:

• The conclusion "Atoms are mostly empty space" and "Most of the mass of the atom is concentrated in the center" were from Rutherford's gold foil experiment, not Thomson's.
• Thomson discovered electrons (negative particles) and proposed the plum - pudding model, realizing that atoms must have positive charge to balance the negative electrons (since atoms are electrically neutral).
• The idea that "Atoms are indivisible" was part of Dalton's atomic theory, and Thomson's experiments showed atoms are divisible (as he discovered electrons). So the correct conclusion from Thomson's experiments is that atoms must balance positive and negative particles.

Answer:

Atoms must balance positive and negative particles.