5.2.4 The Nature of Light

Question 1

photoelectric effect

Answer 1

• Light has properties of both waves and particles.
• light’s ability to excite electrons to higher energy levels. Different wavelengths of light have a different amount of energy that is able to excite electrons into discreet energy levels. This phenomenon is also called photoexcitation. When chlorophyll is hit with UV light, an electron within it gets excited and gains energy. This phenomenon is referred to as photoexcitation.
• When chlorophyll is hit with light, an electron is excited. The electron then falls back down to its ground state
• When the electron falls back down to its ground state, it gives off energy in the form of a photon. Chlorophyll glows red when exposed to UV light.

Question 2

photons

Answer 2

• Light has both wave-like and particle-like properties. Often light is described in wavelengths of energy, but it can also be described as discrete packets of energy

Question 3

Which statement about light is incorrect?

Answer 3

• The wavelength of a photon is directly proportional to its energy

Question 4

The energy content for visible light is greatest for

Answer 4

• green light

Question 5

Light is composed of particles of energy called

Answer 5

• photons

Question 6

Chlorophyll glows red when it is hit with UV light because

Answer 6

• energy is released from an electron that falls to its ground state

Question 7

Visible light ranges between

Answer 7

• 380 to 750 nm.