Which of the following best describes the relationship between the wavelength and frequency of a spectral line for strontium chloride (SrCl_2)?

• A. Wavelength and frequency are independent of each other.
• B. As the wavelength increases, the frequency also increases.
• C. As the wavelength increases, the frequency decreases.
• D. As the frequency increases, the wavelength remains constant.

Answer: (C)

Verified step by step guidance

1. Recall the fundamental relationship between the wavelength (\( \lambda \)) and frequency (\( \nu \)) of electromagnetic radiation, which is given by the equation: \[ c = \lambda \times \nu \] where \( c \) is the speed of light in a vacuum (approximately \( 3.00 \times 10^{8} \) m/s).
2. Understand that the speed of light \( c \) is a constant, so wavelength and frequency are inversely related. This means if one increases, the other must decrease to keep the product \( \lambda \times \nu \) constant.
3. Analyze the options given: - If wavelength and frequency were independent, changing one would not affect the other, which contradicts the constant speed of light. - If both wavelength and frequency increased together, their product would increase, which is impossible since \( c \) is constant. - If frequency increases and wavelength remains constant, their product would increase, again contradicting the constant speed of light.
4. Therefore, the correct conceptual understanding is that as the wavelength increases, the frequency decreases, maintaining the constant speed of light.
5. This inverse relationship applies universally to all electromagnetic radiation, including the spectral lines of strontium chloride (SrCl_2), so the best description is: 'As the wavelength increases, the frequency decreases.'