Final answer:
The wavelength of X-rays with a frequency of 1.0 × 10^19 Hz in air is 3.00 × 10^-11 meters or 0.03 nanometers, calculated using the relationship between the speed of light, frequency, and wavelength.
Step-by-step explanation:
To calculate the wavelength (λ) of X-rays in air given their frequency (f), we use the formula λ = c / f, where c is the speed of light in air (approximately 3.00 × 10^8 m/s). For X-rays with a frequency of 1.0 × 10^19 Hz, the wavelength would be λ = 3.00 × 10^8 m/s / 1.0 × 1019 Hz. Upon performing the division, we find that the wavelength of these X-rays in air is 3.00 × 10^-11 m, which can be converted into nanometers (nm) by multiplying by 10^9 nm/m, resulting in 0.03 nm.