Could something small like a baseball have as much momentum as car

Yes.  Definitely, uh huh, and fer sher.

Momentum is the product of (mass) times (speed).

So it doesn't matter how tiny the mass is.  If the speed is great enough, then the tiny object can have the same momentum as the massive object, or even more.

(That's the whole deal with bullets.)

beta is electron from nucleus

something from nucleus has changed, but charge must be same for cons of charge

k2s for potassium sulphide