1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Nana76 [90]
3 years ago
11

A 100-watt light bulb radiates energy at a rate of 100 J/s. (The watt, a unit of power or energy over time, is defined as 1 J/s.

) If all of the light emitted has a wavelength of 525 nm , how many photons are emitted per second?
Chemistry
1 answer:
Semmy [17]3 years ago
7 0

Answer

2.7956 * 10^19 photons

Givens

  • Wavelength = λ = 525 * 10^-9 meters  [1 nmeter = 1*10^-9 meters]
  • c = 3 * 10^8 meters
  • E = ???
  • W = 100  watts
  • t = 1 second
  • h= plank's Constant = 6.26 * 10^-34 J*s

Formula

E = h * c / λ

W = E / t

Solution

E = 6.26 * 10^-34 j*s * 3 * 10^8 m/s /525 * 10^-9 (m)

The meters cancel out. So do the seconds. You are left with Joules as you should be.

E =  3.577 * 10^-18 Joules

What you have found is the energy of 1 photon.

Now you have to find the Joules from the watts.

W = E/t

100 * 1 second = 100 joules

1 photon contains 3.577 * 10 ^ - 18 Joules

x photon = 100 joules                        

1/x = 3.577 * 10^-18 / 100                          Cross multiply

100 = 3.577 * 10 ^ - 18 * x                         Divide both sides by 3.577 * 10 ^ - 18

100/3.577 * 10 ^ - 18 = 3.577 * 10 ^ - 18x / 3.577 * 10 ^ - 18

2.7956 * 10^19 photons = x


You might be interested in
Which of the following represents positron emission? Select one: a. 3015P ---> 3014Si + ___ b. 23892U ---> 23490Th + ___ c
xxTIMURxx [149]
The simple trick which one can consider in such problem where it is asked for positron emission is :
<span>When the atomic number goes DOWN by one and mass number remains unchanged, then a positron is emitted.
</span>
<span>a.  </span>P^{30}_{15}  ----\ \textgreater \   Si^{30}_{14} + e^{0}_{1}^+
<span>
Here the atomic number decreases by one.

Similarly, options b and d are eliminated.

Option c is also not the answer.
For c, Count the atomic number on left side and compare it with right side. You will see it is 9 on left and 8 on right. Atomic no. did go down by 1. But the atomic mass is changed as well.

</span>
8 0
3 years ago
Two atoms that are isotopes of one another must have the same number of what? Electrons, All Particles, Protons, or Neutrons
emmainna [20.7K]

atoms are made of 3 types of sub atomic particles; neutrons, protons and electrons

atomic number is the number of protons which is characteristic for the element. Atoms of the same element have the same number of protons.

mass number is the sum of the neutrons and protons.

Isotopes are atoms of the same element with different mass numbers. since they are the same element number of protons are the same but number of neutrons vary.

therefore 2 isotopes are of the same element so they have the same number of protons.

5 0
3 years ago
Read 2 more answers
I need to make up an experiment !! Please help
katen-ka-za [31]

Question: Baking a Cake Without Flour.

Hypothesis: I think that when I remove the flour from the standard cake recipe, I'll end up with a flat but tasty cake.

Procedure: I baked two cakes during my experiment. For my control, I baked a cake following a normal recipe. I used the Double Fudge Cake recipe on page 292 of the Betty Crocker Cookbook. For my experimental cake, I followed the same recipe but left out the flour. I first obtained a 2-quart mixing bowl.  

Results: My control cake, which I cooked for 25 minutes, measured 4 cm high.  Eight out of ten tasters that I picked at random from the class found it to be an acceptable dessert. After 25 minutes of baking, my experimental cake was 1.5 cm high and all ten tasters refused to eat it because it was burnt to a crisp.

What did I learn?/Conclusion: Since the experimental cake burned, my results did not support my hypothesis.  I think that the cake burned because it had less mass, but cooked for the same amount of time.  I propose that the baking time be shortened in subsequent trials.

-

I hope this helped :))

7 0
2 years ago
When comparing the colors of the following four compounds, which is most likely to appear green? [Co(CN)6]3− [Co(H2O)6]3+ [Co(en
alexandr1967 [171]

Answer:

3

Explanation:

its bc

5 0
3 years ago
Read 2 more answers
What was the open-range system ​
Nesterboy [21]

Answer: In the Western United States and Canada, open range is rangeland where cattle roam freely regardless of land ownership. ... Land in open range that is designated as part of a "herd district" reverses liabilities, requiring an animal's owner to fence it in or otherwise keep it on the person's own property.

Explanation: Mark me as brainliest

5 0
3 years ago
Other questions:
  • The reaction 2 no(g) + cl2(g) → 2 nocl(g) is carried out in a closed vessel. if the partial pressure of no is decreasing at a ra
    9·1 answer
  • What objects do magnets stick to?
    10·2 answers
  • Explain the difference betweeen mass and volume
    13·1 answer
  • Cindy made tea. She started with 300 grams of water at 20 degrees Celsius. She transferred 18,000 calories to the water. What wa
    11·1 answer
  • Which statement defines calorimetry
    9·2 answers
  • Given the reaction:
    14·1 answer
  • 5. What if the single replacement reaction involves a nonmetal added to a solution?
    8·1 answer
  • Isocyanates are good electrophiles that have been used for protein modification. However, they have limited stability in water.
    14·2 answers
  • Ionization energies tend to do what across a period
    12·1 answer
  • AAAAAAAAAAAAAA MATIAS IS HERERERERE
    8·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!