Question

What two methods are used in the lab to excite electrons?

Using Plank's equation, calculate the energy corresponding to:
a. a wavelength of 578.6 nanometers.
b. a wavelength of 4.521 x 10-7 meters.
3. List five areas/regions of the electromagnetic spectrum and at least one application of each area you listed. ​

Answer 1

In laboratories, electrons are excited by electric current or light absorption. Using Planck's equation, energies for the given wavelengths are 3.44 × 10-19 Joules and 4.39 × 10-19 Joules. The electromagnetic spectrum includes radio waves, microwaves, infrared, visible light, and ultraviolet, each with distinct applications.

Step-by-step explanation:

In the lab, electrons can be excited using two primary methods: by passing an electric current through gases or by absorbing light at the appropriate wavelength (or frequency). These methods cause electrons to 'jump' to higher energy levels.

Using Planck's equation (E = hc/λ), where 'h' is Planck's constant (6.626 × 10-34 Js), 'c' is the speed of light (3 × 108 m/s), and 'λ' is the wavelength, we can calculate the energy of photons:

1. For a wavelength of 578.6 nanometers (5.786 × 10-7 meters), the energy (E) = (6.626 × 10-34 Js) × (3 × 108 m/s) / (5.786 × 10-7 m) = 3.44 × 10-19 Joules.
2. For a wavelength of 4.521 × 10-7 meters, the energy (E) = (6.626 × 10-34 Js) × (3 × 108 m/s) / (4.521 × 10-7 m) = 4.39 × 10-19 Joules.

There are several areas/regions of the electromagnetic spectrum:

• Radio waves - Used for broadcasting and communications.
• Microwaves - Used for cooking and satellite transmissions.
• Infrared - Used for night-vision devices and heat sensing.
• Visible light - Enables sight, photography, and illumination.
• Ultraviolet - Used for sterilization and fluorescence.