Answer:
Helium, Neon, Argon, Krypton, Xenon, Radon, and Oganesson
Explanation:
they have full outer shells
Answer: O 10.1 is your answer! Please mark me as brainlyest!?
Answer:
- <u>2.59 × 10⁻⁷ m = 259 nm</u>
Explanation:
You need to calculate the wavelength of a photon with an energy equal to 463 kJ/mol, which is the energy to break an oxygen-hydrogen atom.
The energy of a photon and its wavelength are related by the Planck - Einstein equation:
Where:
- h = Planck constant (6.626 × 10⁻³⁴ J . s) and
- ν = frequency of the photon.
And:
Where:
- c = speed of light (3.00 × 10⁸ m/s in vacuum)
- λ = wavelength of the photon
Thus, you can derive:
Solve for λ:
Before substituting the values, convert the energy, 463 kJ/ mol, to J/bond
- 463 kJ/ mol × 1,000 J/kJ × 1 mol / 6.022 × 10 ²³ atom × 1 bond / atom
= 7.69×10²³ J / bond
Substitute the values and use the energy of one bond:
- λ = 6.626 × 10⁻³⁴ J . s × 3.00 × 10⁸ m/s / 7.69×10²³ J = 2.59 × 10⁻⁷ m
The wavelength of light is usually shown in nanometers:
- 2.59 × 10⁻⁷ m × 10⁹ nm / m = 259 nm ← answer
It shows mass is not created nor lost but re arranged
The volume of concentrated HCl : 2.073 ml
<h3>Further explanation</h3>
Given
37% HCl by mass; density 1.19 g/mL
Required
The volume of concentrated HCl
Solution
Conversion to molarity :
37% x 1.19 g/ml =0.4403 g/ml
g/ml to mol/L :
=0.4403 g/ml x 1000 ml/L : 36.5 g/mol
=12.06 mol/L
or we can use formula :
Dilution formula :
M₁V₁=M₂V₂
12.06 M x V₁ = 0.1 M x 0.25 L
V₁ = 0.0021 L = 2.073 ml
