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
Number 1 is c. because objects reflect light we see it.
<h3>
Answer:</h3>
Homogeneous mixture with components of different boiling points
<h3>
Explanation:</h3>
- Distillation is a method of separating miscible mixtures which contain components that have different boiling points.
- The mixture is heated and the component with the low boiling point evaporates first. It is then condensed in the condenser and the distillate collected using a clean beaker.
- For example, a miscible solution of ethanol and water can be separated using distillation.
- Ethanol and water have different boiling points of 78°C and 100°C respectively. Ethanol is distilled out first because it has a low boiling point compared to water.
