Answer:
Explanation:
When an electron jumps from one energy level to a lower energy level some energy is released in the form of a photon.
The difference in energy between the two levels is the energy of the photon and that energy is related to the frequency of the photon by the Einstein - Planck equation:
Where,
- E = energy of the photon,
- h = 6.626×10⁻³⁴ J.s, Planck constant, and
- ν = frequency of the photon.
So, to find the frequency you must first find the energy.
The transition energy can be calculated using the formula:
Where E₀ = 13.6 eV ( 1 eV = 1.602×10⁻¹⁹ Joules) and n = 1,2,3,...
So, the transition energy between n = 4 and n = 3 will be:
- ΔE = - E₀ [ 1/4² - 1/3²] = - 13.6 eV [1/16 - 1/9] = 0.6611. . .eV
- ΔE = 1.602×10⁻¹⁹ Joules/eV × 0.6611... eV = 1.0591 ×10⁻¹⁹ Joules
Now you can use the Einstein - Planck equation:
- ν = 1.0591 ×10⁻¹⁹ J / 6.626×10⁻³⁴ J.s = 1.60×10¹⁴ s⁻¹ (rounded to 3 significant figures).
In 2009, the US Geological Survey estimated the Arctic may be home to 30% of the planet's natural gas reserves and 13% of oil.
Answer:
3.14
Explanation:
A student was comparing two samples with an equal number of carbon atoms. One sample contained only Carbon-12 atoms. One sample contained only Carbon-14 atoms, which contain two more neutrons than Carbon-12 atoms. The student measured the mass of each sample and testing the reactivity of each sample.
Required:
What would best describe the results of the investigation?
Volumetric flask is the most accurate because making solutions often requires very exact volumes. Graduated cylinders are next most accurate because they can be nade thin and thus very precise. Beakers are least accurate because they are thick and extremely accurate measurements are not usually needed in beakers so manufacturers are generally less precise.