D IS THE ANSWER TO YOUR QUESTION
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
Answer:
A
Explanation:
because it loses 2 electrons
Answer:
Cement is a combination of calcium, silicone, aluminum, iron and lots of other ingredients to make side walks, home made crafts, etc. The person who invented concrete is Joseph Aspdin.
Explanation:
Answer:
about 0.9 mol
Explanation:
there are 22.990 g/mol of Na
20.7/22.99 = 0.900391 mol
about 0.9 mol
