Front and back is a synonym or a antonyms

Match the following items. 1. high-intensity bundle of energy being emitted from some decaying nuclei gamma ray 2. particle radiating from the nucleus of some atoms beta particle 3. negative particle identical to an electron but radiating from a decaying nucleus alpha particle

How many valence electrons are in atom of radon?

Calculate the concentration of all species in a 0.165 m solution of h2co3.