Question

what did j.j. thomsons experiments with cathode ray tubes imply about the mass of an electron?
electrons are many thousand times larger than the nucleus and negatively charged.
electrons are many thousand times smaller than the nucleus and positively charged.
electrons are many thousand times smaller than the nucleus and negatively charged.
electrons are many thousand times larger than the nucleus and possess no charge.

Explanation:

J.J. Thomson's cathode - ray tube experiments showed electrons are negatively charged and much smaller in mass compared to the nucleus.

Answer:

Electrons are many thousand times smaller than the nucleus and negatively charged.