What does it mean for the energy levels in an atom to be quantized? Describe how this affects where electrons can be found.

Energy of an electron is quantinized means the electrons can possess only specific individually separated values.

These energy levels are stable and are stationary along with different energy value.  The electron remains in the state until energy is absorbed or released.

The electrons absorb energy when it moves from lower energy state to higher energy state. The electrons lose energy when it moves from higher energy state to lower energy state and thus emit radiations corresponding to the energy gap and is called as quanta.

altitude, density, pressure

air gets less dense the higher the altitude and also the air pressure is less as altitude rises.

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