Atoms, nuclei and radiation

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Across
  1. 1. Has a mass of 4 amu
  2. 3. This number is conserved
  3. 6. Has different number of neutrons
  4. 11. These are produced during β– decay
  5. 12. Particles with a continuous range of energies
Down
  1. 2. This is the antiparticle of an electron
  2. 4. These are produced during β+ decay
  3. 5. Alpha particles have this energy
  4. 7. Electrons are in _______ around the nucleus
  5. 8. The correct unit of mass is the _______ mass unit
  6. 9. Discovered with alpha particle scattering
  7. 10. Most penetrating radiation