Which of the following best represents and explains the formula for a compound made from nitrogen and hydrogen? NH4, because nitrogen needs four electrons, and each hydrogen needs one electron.
NH4, because nitrogen needs one electron, and each hydrogen needs four electrons.
NH3, because nitrogen forms a triple bond with each hydrogen atom.
NH3, because nitrogen forms a single bond with each hydrogen atom.

Many radioactive atoms that have large masses undergo radioactive decay by releasing a particle that is identical to a helium-4 nucleus. what changes in the original atom are expected as a result of this natural phenomenon? the atomic number and the mass number will decrease. the atomic number and the mass number will increase. the atomic number will increase, and the mass number will decrease. the atomic number will decrease, and the mass number will increase.