The half-life of radon-222 is 3.8 days. How many grams of radon-222 remain

Calculate the wavelength, in nanometers, of the light emitted by a hydrogen atom when its electron falls from the n = 7 to the n

Gre4nikov [31]

Answer:

The wavelength of the light emitted by a hydrogen atom for the given transition is 2166 nm.

Explanation:

The energy of nth energy levels of the H atom is given as:

$E_n = -2.18 \times 10^{-18} \times \frac{1}{n^2} J$

Energy of the seventh energy level = $E_7$

$E_7=-2.18 \times 10^{-18} \times \frac{1}{7^2} J$

$E_7=-2.18 \times 10^{-18} \times \frac{1}{7^2} J=-4.4490\times 10^{-20} J$

Energy of the seventh energy level = $E_4$

$E_4=-2.18 \times 10^{-18} \times \frac{1}{4^2} J$

$E_4=-2.18 \times 10^{-18} \times \frac{1}{16} J=-1.3625\times 10^{-19} J$

Energy of the light emitted will be equal to the energy difference of the both levels.

$E=E_7-E_4=-4.4490\times 10^{-20} J-(-1.3625\times 10^{-19} J)$

$E=9.176\times 10^{-20} J$

Wavelength corresponding to energy E can be calculated by using Planck's equation:

$E=\frac{hc}{\lambda }$

$\lambda =\frac{hc}{E}=\frac{6.626\times 10^{-34} Js\times 3\times 10^8 m/s}{9.176\times 10^{-20} J}=2.166\times 10^{-6} m=2166 nm$

The wavelength of the light emitted by a hydrogen atom for the given transition is 2166 nm.

8 0

3 years ago

Acids, when mixed with water, do which of the following... A Taking away protons from the water molecules B Giving away protons

pav-90 [236]

Answer:

Giving away protons to the water molecules

Explanation:

When acids are mixed with water the following reaction takes place:

H^+(aq) + H2O(l) ------> H3O^+(aq)

Hence when acids are added to water, acids donate a proton to water to form the oxonium ion H3O^+ by coordinate covalent bonding. Note that acids contain the hydrogen ion H^+

4 0

3 years ago

From which source is pomace derived? (1 point)

GrogVix [38]

Answer: unused waste from food processing

Explanation: have you takin the chemical reaction system unit test yet? It’s alternated

6 0

3 years ago

A beam of light passes though a liquid in a test tube without scattering. Which type of mixture is most likely in the test tube?

butalik [34]

The answer would be letter C - solution.

A mixture should be homogeneous for a light not to be scattered. This is because particles are distributed evenly throughout the mixture which allows light to pass directly. In your choices, the solution allows a beam of light to pass through a liquid in a test tube without scattering.

6 0

4 years ago

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The development of a nuclear power plant at an ocean site is expected to produce an enormous amount of electric power for a larg

Oksanka [162]

Answer:

B. The effects of warmed water on aquatic life

Explanation:

quizizz

8 0

3 years ago

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