The noble gases are helium, neon, argon, krypton, xenon, radon, and ununoctium. The noble gases are relatively nonreactive. This is because they have a completevalence shell<span>. They have little tendency to </span>gain<span> or lose </span>electrons. <span>These gases all have similar properties under standard conditions: they are all odorless, colorless, monatomic gases with very low chemical </span>reactivity<span>. The six noble gases that occur naturally are helium (He), Neon (Ne), Argon (Ar), Krypton (Kr), Xenon (Xe), and Radon (Rn).</span>
The molecular weight is the same as molecular mass. You find this by using the periodic table
The molar mass of Mg(NO3)2 is 148.3
Periodic table of elements
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