The component of an atom that contributes least to its mass is the? by Sunday | Oct 14 | Chemistry JAMB | 0 comments A. proton B. nucleus C. neutron D. electron Correct Answer: Option D – electron Users Also Read These:An atom W has 17 electrons and 18 neutrons. Which of…The atomic number of an atom would be equal to its…In the upper atmosphere, the ultra-violet light…An atom X consists of 6 protons, 6 electrons and 7…The nucleon number and the proton number of a…