Model atoma (aktivni)
Borov model
Borov model atoma predstavlja atom sa malim pozitivno naelektrisanim jezgrom oko kojeg se elektroni kreću u kružnim orbitama, slično kretanju planeta oko Sunca. Dakle, po Borovom modelu, atom je sličan planetarnom sistemu koji je već dao Raderford. Njegova teorija je testirana i primenjena na vodonikovom atomu, ali nije mogla da se primeni na ostalim atomima. Bor je Raderfordov model dopunio sa svoja tri postulata.
1. Postulat stacionarnih orbita.
2. Momenat impulsa ima strogo diskretne vrednosti.
3. Prilikom prelaska elektrona na više ili niže energetske nivoe dolazi do apsopcije ili emisije elektromagnetnog zračenja.

Kvantnomehanički model atoma
Elektron se u atomu kreće u veoma malom prostoru i zbog toga se u atomu ispoljavaju njegova talasna svojstva. Kada je elektron slobodan, u gasnoj cevi ili strujnom provodniku, onda se ispoljavaju njegova čestična svojstva. Pošto elektron u atomu ispoljava talasna svojstva, njegovo kretanje i njegova stanja opisuju talasne funkcije. To zapravo znači da uobičajene predstave modela atoma koje vidiš i u našem Parku nisu zapravo precizne i da je potrebno da istražiš ovaj kvantno mehanički model atoma.
AKTIVNOST: Dok se ne konsultuješ sa Internetom i otkriješ kvantno-mehanički model atoma, pokušaj da nanižeš modele nekih atoma, koristeći kuglice različitih boja koje predstavljaju protone, neutrone i elektrone. U jezgro stavi nukleone (protone i neutrone), a na metalni obruč naniži elektrone.
Napravi za početak:
1H1 2He4 3Li6 možeš se „igrati“ sve do kiseonika 8O16



Model of the atom (active)

Bohr model
            The Rutherford-Bohr model or Bohr model depicts the atom as a small, positively charged nucleus surrounded by electrons that travel in circular orbits similar in structure to the Solar System. According to Bohr model, the atom is similar to planets orbiting the sun, the system that had already been presented by Rutherford. His theory was tested and applied to the hydrogen atom, but it could not be applied to other atoms. Bohr added three postulates to the Rutherford model:

  1. Postulate of stationary orbits.
  2. Angular momentum has discrete values.
  3. At the transition of an electron to higher or lower energy levels, electromagnetic radiation is either absorbed or emitted.

Quantum mechanics and the model of the atom

Electron moves in the atom in an extremely small space, and therefore the wave properties of the atom are expressed. When the electron is free in a gas tube or in a conductor, his particle properties are expressed. Since electron shows his wave properties in the atom, its movement and its conditions are described by wave functions. This actually means that usual models of the atom which you can see in our Park are not precise and that you have to examine the quantum mechanical model of the atom.

ACTIVITY: Until you consult the Internet and discover the quantum-mechanical model of the atom, try to make models of certain atoms using different colour balls that represent protons, neutrons and electrons. Place nucleons (protons and neutrons) into the core, and electrons on the metal ring.

For a start, you can make this:

1H1  2He4 3Li6 you can “play” all through oxygen 8О16