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g100num [7]
3 years ago
8

What is the wavelength of an X-ray that has a frequency of 7.8 x 1017 Hz

Chemistry
1 answer:
SVEN [57.7K]3 years ago
3 0

Answer:

λ = 0.38 ×10⁻⁹ m

Explanation:

Given data:

Wavelength of xray = ?

Frequency of xray = 7.8 ×10¹⁷ Hz

Solution:

Formula:

Speed of light = wavelength × frequency

speed of light = 3×10⁸ m/s

Now we will put the values in formula.

3×10⁸ m/s = λ × 7.8 ×10¹⁷ Hz

λ = 3×10⁸ m/s / 7.8 ×10¹⁷ Hz

         Hz = s⁻¹

λ = 3×10⁸ m/s / 7.8 ×10¹⁷s⁻¹

λ = 0.38 ×10⁻⁹ m

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The molecular weight of a gas is ________ g/mol if 3.5 g of the gas occupies 2.1 l at stp
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