Answer:
7.05 × 10⁻²² nm
Explanation:
Step 1: Given and required data
- Energy evolved when a mole of electrons changes between the 2 levels (E): 282 kJ
- Planck's constant (h): 6.63 × 10⁻³⁴ J.s
- Speed of light (c): 3.00 × 10⁸ m/s
Step 2: Calculate the wavelength (λ) of the light evolved
We will use Planck-Einstein's relation.
E = h × c/λ
λ = h × c/E
λ = (6.63 × 10⁻³⁴ J.s) × (3.00 × 10⁸ m/s)/(282 × 10³ J) = 7.05 × 10⁻³¹ m
We will convert λ to nm using the conversion factor 1 m = 10⁹ nm.
7.05 × 10⁻³¹ m × 10⁹ nm/1 m = 7.05 × 10⁻²² nm
Answer:
C meteoroid
Explanation:
Meteoroids are the only ones of the four that are under a kilometer in size.
Answer:
1.90 M
Explanation:
To find the molarity of the solution, you need to use the molarity equation. This formula looks like this:
Molarity (M) = moles / volume (L)
To use this equation, you need to perform some conversions. You should (1) convert mL to L (by dividing by 1,000), then (2) convert grams NaNO₃ to moles (via molar mass), then (3) plug moles and volume into the molarity equation.
155 mL / 1,000 = 0.155 L
25.0 g NaNO₃ 1 mole
--------------------- x ----------------- = 0.294 moles NaNO₃
85.0 g
Molarity = moles / volume
Molarity = 0.294 moles / 0.155 L
Molarity = 1.8975....
Molarity = 1.90 M
It’s is a pure substance because nothing is mixed with it and a molecule gas because it’s is a gas and it’s by its self