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To calculate the number of photons, you need the formula E=hf where h is Planck's constant with a value of 6.63*10^-34Js and f should be given.
If f isn't given, then use the formula C = f * wavelength. Rearrange this formula by using the wavelength given and the C, speed of light, which is 3*10^8.
You should get C/wavelength = f, which will then be placed into E=hf => answer.
What you also need is the Intensity. This way you obtain the photon flux as: I/E (i.e. the number of photons per unit area and unit time).
Wiki User
∙ 11y ago
Wiki User
∙ 13y agoEnergy content would be measured in Joule. Mole is a measure of "quantity of substance", basically, counting or calculating the number of photons. It is not related to energy content.
Wiki User
∙ 14y agoMultiply the photon's frequency by Planck's constant.
Planck's constant is [ 6.626 x 10-34 Joule-second ] (rounded)
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How do you calculate how much energy in kJ do 3.0 moles of photons all with a wavelength of 655 nm contain?
The energy is 18,263.10e4 joules.
How much energy in kJ do 3.0 moles of photons all with a wavelength of 655 nm contain?
548kJ
How do you calculate energy per mole of photons if you know joules per photon?
You have to multiply the joules/photon by Avogadro's Number, i.e., by the number of particles in a mole.
How many moles of photons with a wavelength of 660 nm are needed to provide 6 kJ of energy?
The energy carried by a photon is given byE = hfWhere h is Planck's constant (6.626x10^-34 Joule-seconds) and f is the frequency of the photon in Hertz (Hz).We are given the wavelength of the photon in the question in nanometers (nm). First, we need to convert this to (SI) units, because our equations only work with SI units. Then, we will calculate the frequency of the photon from its wavelength. Once we know the frequency of the photon we're interested in, we simply use the equation above to find the energy carried by one of them. Then we divide 6 kJ by that amount of energy, and the quotient will be the number of photons needed to carry 6 kJ. Finally, when we know the number of photons we need, we divide by the number of photons in a mole to get the number of moles.The SI unit of length is the meter (m). 1nanometer (nm) is 10^-9 meters.660 nm = 660 *10^-9 m = 6.6*10^-7 m.Now we will calculate this photon's frequency from its wavelength. These are related by the equationc = fLwhere c is the speed of light (3*10^8 m/s), f is the frequency of the photon and L is the wavelength of the photon.c = fL(3*10^8 m/s) = f * (6.6*10^-7 m)solving for f, we havef = (3*10^8 m/s) / (6.6*10^-7 m) = 4.54*10^15 s^-1Note that the unit of seconds (s) raised to the -1power is defined as 1 Hertz (Hz).f = 4.54*10^15 HzNow we will use the top equation to solve for the energy carried by one photon having this frequency.E = hfE = (6.626*10^-34 Js) * (4.54*10^15 Hz)E = 1.369*10^-17 JThis is how much energy is carried by one photon of wavelength 660 nm (which will also have a frequency of 4.54*10^15 Hz).How many of these do we need to provide 6 kJ? This is solved by simple division. Keeping in mind that 1 kJ = 1000 J, we haveNumber of photons * Energy per photon = 6 kJNumber of photons * (1.369*10^-17 J/photon) = 6 kJNumber of photons * (1.369*10^-17 J/photon) = 6000 JNumber of photons = 6000 J / (1.369*10^-17 J/photon)Number of photons = 4.382*10^20 photonsThis is how many photons (at this frequency) are needed to provide 6 kJ. How many moles of photons is this?Number of photons / number of photons in a mole = number of molesRecall that a mole of something is defined as 6.02*10^23of it. The same way a dozen eggs is defined as 12 eggs, a mole of eggs is 6.02*10^23 eggs. Equivalently, a mole of photons is 6.02*10^23 photons. SoNumber of photons / (6.02*10^23 photons per mole) = number of moles(4.382*10^20 photons) / (6.02*10^23 photons per mole) = number of moles7.279*10^-4 moles = number of molesForgive me if my arithmetic is off, as I don't have a good calculator handy. However, I believe this is the correct method to use.
Calculate the number of moles in 2400g of Co2?
54.54 moles
How do you calculate how much energy in kJ do 3.0 moles of photons all with a wavelength of 655 nm contain?
The energy is 18,263.10e4 joules.
How much energy in kJ do 3.0 moles of photons all with a wavelength of 655 nm contain?
548kJ
How do you calculate energy per mole of photons if you know joules per photon?
You have to multiply the joules/photon by Avogadro's Number, i.e., by the number of particles in a mole.
How do you calculate moles from molarity?
Number of Moles = concentration * volume (in litres)
How many moles of photons with a wavelength of 660 nm are needed to provide 6 kJ of energy?
The energy carried by a photon is given byE = hfWhere h is Planck's constant (6.626x10^-34 Joule-seconds) and f is the frequency of the photon in Hertz (Hz).We are given the wavelength of the photon in the question in nanometers (nm). First, we need to convert this to (SI) units, because our equations only work with SI units. Then, we will calculate the frequency of the photon from its wavelength. Once we know the frequency of the photon we're interested in, we simply use the equation above to find the energy carried by one of them. Then we divide 6 kJ by that amount of energy, and the quotient will be the number of photons needed to carry 6 kJ. Finally, when we know the number of photons we need, we divide by the number of photons in a mole to get the number of moles.The SI unit of length is the meter (m). 1nanometer (nm) is 10^-9 meters.660 nm = 660 *10^-9 m = 6.6*10^-7 m.Now we will calculate this photon's frequency from its wavelength. These are related by the equationc = fLwhere c is the speed of light (3*10^8 m/s), f is the frequency of the photon and L is the wavelength of the photon.c = fL(3*10^8 m/s) = f * (6.6*10^-7 m)solving for f, we havef = (3*10^8 m/s) / (6.6*10^-7 m) = 4.54*10^15 s^-1Note that the unit of seconds (s) raised to the -1power is defined as 1 Hertz (Hz).f = 4.54*10^15 HzNow we will use the top equation to solve for the energy carried by one photon having this frequency.E = hfE = (6.626*10^-34 Js) * (4.54*10^15 Hz)E = 1.369*10^-17 JThis is how much energy is carried by one photon of wavelength 660 nm (which will also have a frequency of 4.54*10^15 Hz).How many of these do we need to provide 6 kJ? This is solved by simple division. Keeping in mind that 1 kJ = 1000 J, we haveNumber of photons * Energy per photon = 6 kJNumber of photons * (1.369*10^-17 J/photon) = 6 kJNumber of photons * (1.369*10^-17 J/photon) = 6000 JNumber of photons = 6000 J / (1.369*10^-17 J/photon)Number of photons = 4.382*10^20 photonsThis is how many photons (at this frequency) are needed to provide 6 kJ. How many moles of photons is this?Number of photons / number of photons in a mole = number of molesRecall that a mole of something is defined as 6.02*10^23of it. The same way a dozen eggs is defined as 12 eggs, a mole of eggs is 6.02*10^23 eggs. Equivalently, a mole of photons is 6.02*10^23 photons. SoNumber of photons / (6.02*10^23 photons per mole) = number of moles(4.382*10^20 photons) / (6.02*10^23 photons per mole) = number of moles7.279*10^-4 moles = number of molesForgive me if my arithmetic is off, as I don't have a good calculator handy. However, I believe this is the correct method to use.
Calculate the number of moles in 2400g of Co2?
54.54 moles
calculate the number of moles in H2 molecules in 4g H2?
2 moles.
How do you calculate moles of ions in 0.200 moles aluminum perchlorate.?
0,6 moles of (ClO4)3- and 0,2 mol Al
How can you use moles to solve problems?
moles can be used to calculate gmv(gram molecular weight)
How do you calculate the moles of water?
You use the formula concentration x volume to find out the number of moles
How many moles are in 1.5 grams of iron?
To calculate the number of moles from grams, you must divide by the substance's molar mass
How do you calculate the mass of an object in a chemical equation?
balance your chemical reaction equation then calculate moles, then calculate weight.
