All the subatomic particles participate in chemical reactions. a. true b. false

Nope. Only electrons take part in the "chemical reaction".
But if you collide two particles at the speed of light or close to it, then protons, neutrons and in fact other subatomic particles also take part in the reaction. PS: this is not a chemical reaction, it is called nuclear reaction.
You need to accelerate particles at the ultimate speed because protons and neutrons are strongle held inside nucleus because of "strong force"

Mass is the amount of matter in an object.  weight is the measurement of the pull of gravity on an object.  say for example, you travel to the moon which has a different gravitational field compared to the gravitational field of earth. (gravitational fields: earth = 1, moon = 0.165)  now when you are on the moon, the pull of gravity on you is different than on the earth. and as weight is the measurement of the pull of gravity on an object, that means yes, your weight can and will change on the moon.  however, on the moon, on earth or even on jupiter, the amount of mass inside of you remains the same. meaning your physical mass remains constant.  in conclusion it is possible for your weight to change as your mass remains constant.