4. Someone proposes to make a new LED using gallium and antimony. What would you predict about its band gap relative to the LEDs in the table? **How Light Emitting Diodes (LEDs) Work**Light emitting diodes generate light through an electrical circuit where electrons transition across a "band gap" from a high energy state to a lower energy state. The size of the band gap determines the energy and color of the emitted light. A larger band gap results in greater energy emission as photons (particles of light), producing blue light, while a smaller energy change results in red light.To emit visible light, LEDs combine different elements to adjust the band gap. Pure elements alone emit energy outside the visible spectrum. The table below outlines the composition and properties of LEDs using different elemental combinations.**Table 1: Composition and Properties of LEDs**| Element 1 | Element 2 | Size of Band Gap | LED Color ||-----------|--------------|------------------|-----------|| Gallium | Nitrogen | Large | Blue || Gallium | Phosphorous | Medium | Green || Gallium | Arsenic | Small | Red |This table shows how mixing gallium with nitrogen, phosphorous, or arsenic affects the band gap size and consequently the color of light emitted by the LED.

The bandgap energy of a semiconductor is related to its composition. The important trend that can be observed here is that moving down in a group of the periodic table, there is a decrease in the energy gap of the group’s elements. This is because the energy gap is related to the splitting of the energy between the bonding orbitals and antibonding orbitals. Gallium is a member of group 13 elements of the periodic table. Whereas the elements of the column Element 2 of table 1 are the group 15 elements of the periodic table. As stated above, band energy decreases as we go down a group, the decrease in the size of bandgap can be observed in table 1. Antimony is the next member of group 15 elements in the periodic table after Arsenic thus, it has a lower energy gap as compared to the elements above it. Therefore, the Gallium and Antimony LED will have a very small size of bandgap comparative to the LEDs of table 1.