Chemistry, 06.10.2019 05:30 kaylarae1930

Consider the following energy levels of a hypothetical atom: e4 −1.21 × 10−19 j e3 −5.71 × 10−19 j e2 −1.05 × 10−18 j e1 −1.55 × 10−18 j (a) what is the wavelength of the photon needed to excite an electron from e1 to e4? (b) what is the energy (in joules) a photon must have in order to excite an electron from e2 to e3? (c) when an electron drops from the e3 level to the e1 level, the atom is said to undergo emission. calculate the wavelength of the photon emitted in this process.

Answers: 1

Show answers

Answers

Answer from: Momorin5625

Explanation:

Energy levels of a hypothetical atom:

$E_4 =-1.21\times 10^{-19} J$

$E_3 =-5.71\times 10^{-19} J$

$E_2 =-1.05\times 10^{-18} J$

$E_1 =-1.55\times 10^{-18} J$

a) Wavelength of the photon needed to excite an electron from E_1 to E_4 .

Energy difference between forth and first energy level =

$E=E_4-E_1=(-1.21\times 10^{-19} J )-(-1.55\times 10^{-18} J)=1.429\times 10^{-18} J$

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

$\lambda =\frac{hc}{E}=\frac{(6.634\times 10^{-34}Js)\times (3\times 10^8m/s)}{1.429\times 10^{-18} J}$

$=1.392\times 10^{-7} m=139.2 nm$

139.2 nm is the wavelength of the photon needed to excite an electron from E_1 to E_4 .

b) Energy of a photon in order to excite an electron from E_2 to E_3 .

Energy difference between third and second energy level =

$E=E_3-E_2=(-5.71\times 10^{-19} J)-(-1.05\times 10^{-18} J)=4.79\times 10^{-19} J$

$4.79\times 10^{-19} J$ is the energy a photon to excite an electron from E_2 to E_3 .

c) Electron drops from the E_3 level to the E_1 level

Energy difference between third and first energy level =

$E=E_3-E_1=(-5.71\times 10^{-19} J )-(-1.55\times 10^{-18} J)=9.79\times 10^{-19} J$

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

$\lambda =\frac{hc}{E}=\frac{(6.634\times 10^{-34}Js)\times (3\times 10^8m/s)}{9.79\times 10^{-19} J}$

$=2.033\times 10^{-7} m=203.3 nm$

202.3 nm is the wavelength of the photon of emitted.

Answer from: Quest

Answer: abeexplanation:

1. the question asks the most appropriate, which seems to rule out "all of the above." your choice appears to be the correct one.

2. the protocol described is good for identifying correlation, but not cause and effect. for cause/effect, you need to devise a protocol that will assign the treatment (or not) to groups that have essentially the same "demographics" with respect to all the other variables. your choice regarding control group seems appropriate. random assignment of treatment (choice d) may be appropriate also. (i think you can argue that b and d are just different descriptions of the same method.)

3. d will randomize the birds, but may not guarantee there are 10 in each group. e will do both, so seems the better choice.

comment on question 2

based on the problem statement, it seems clear that confident, attentive drivers are more likely to use daytime running lights. so, the protocol might need to be devised in such a way that the lights would be turned on or off without the driver's knowledge. (an attentive driver will figure it out.) assigning a confident, attentive driver to a group required to drive without running lights might mess with his/her confidence and attentiveness. you don't want your experiment to do that. (nor do you want the experiment to subject a driver to greater risk of accident as a consequence of driving without running lights.) experiments involving human safety are always problematic.

Answer from: Quest

Adozen is 12, and your needing to calculate the weight of one medium egg, so i would do 21/12=1.75 per egg, and check your answer by doing 1.75 * 12= 21 : ) : ): ): ): ) i hoped i

Another question on Chemistry

Chemistry, 22.06.2019 03:30

At a temperature of 393 k, the temperature of a sample of nitrogen is 1.07 atm what will the pressure be at a temperature of 478 k

Answers: 1

Answer

Chemistry, 22.06.2019 17:00

The arrangement of particles is most ordered in a sample of

Answers: 1

Answer

Chemistry, 22.06.2019 21:30

Which statement are accurate about snow flakes

Answers: 1

Answer

Chemistry, 22.06.2019 21:40

A5 mole sample of liquid acetone is converted to a gas at 75.0°c. if 628 j are required to raise the temperature of the liquid to the boiling point, 15.600 kj are required to evaporate the liquid, and 712 j are required to raise the final temperature to 75.0°c, what is the total energy required for the conversion?

Answers: 3

Answer

You know the right answer?

Consider the following energy levels of a hypothetical atom: e4 −1.21 × 10−19 j e3 −5.71 × 10−19 j e...

Questions