Problem 16 - Chemistry: The Central Science

Question

Determine which of the following statements are false and correct them. (a) The frequency of radiation increases as the wavelength increases. (b) Electromagnetic radiation travels through a vacuum at a constant speed, regardless of wavelength. (c) Infrared light has higher frequencies than visible light. (d) The glow from a fireplace, the energy within a microwave oven, and a foghorn blast are all forms of electromagnetic radiation.

Step-by-Step Solution

Answer

(a) False. The corrected statement is: "The frequency of radiation decreases as the wavelength increases." (b) True. Electromagnetic radiation travels at the speed of light in a vacuum, regardless of its wavelength. (c) False. The corrected statement is: "Infrared light has lower frequencies than visible light." (d) Partially true. The corrected statement is: "The glow from a fireplace and the energy within a microwave oven are forms of electromagnetic radiation, but a foghorn blast is not."

Step 1: (a) Examining the relationship between frequency and wavelength

The statement says: "The frequency of radiation increases as the wavelength increases." This is not true because the frequency of radiation and wavelength are inversely proportional to each other. According to the formula \(c = \lambda\nu\), where 'c' is the speed of light, '\(\lambda\)' is the wavelength, and '\(\nu\)' is the frequency, an increase in wavelength leads to a decrease in frequency. Therefore, the corrected statement is: "The frequency of radiation decreases as the wavelength increases."

Step 2: (b) Considering the speed of electromagnetic radiation in a vacuum

The statement says: "Electromagnetic radiation travels through a vacuum at a constant speed, regardless of wavelength." This statement is true. Electromagnetic radiation travels at the speed of light (approximately \(3.0 \times 10^8\) meters per second) in a vacuum, regardless of its wavelength.

Step 3: (c) Comparing the frequencies of infrared and visible light

The statement says: "Infrared light has higher frequencies than visible light." This statement is false. Infrared light has lower frequencies compared to visible light. The electromagnetic spectrum is organized from lower to higher frequencies as follows: radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays. Thus, the corrected statement is: "Infrared light has lower frequencies than visible light."

Step 4: (d) Identifying different forms of electromagnetic radiation

The statement says: "The glow from a fireplace, the energy within a microwave oven, and a foghorn blast are all forms of electromagnetic radiation." This statement is partially true. The glow from a fireplace is a form of electromagnetic radiation, specifically infrared radiation. The energy within a microwave oven is also a form of electromagnetic radiation, specifically microwaves. However, a foghorn blast is not a form of electromagnetic radiation but rather sound waves, which are mechanical waves that travel through a medium like air or water. Therefore, the corrected statement is: "The glow from a fireplace and the energy within a microwave oven are forms of electromagnetic radiation, but a foghorn blast is not."