Answer please ASAP ASAP it’s due today!?!

Chemistry

1 answer:

stira [4]3 years ago

8 0

Answer:

Atoms are composed of extremely small particles that are too small to be seen with an optical microscope.

Size at the atomic level is measured on the nanoscale.

Atoms are made of three subatomic particles - protons, neutrons, and electrons.

Protons:

positively charge
located in the nucleus

Neutrons:

no charge (neutraly charge)
located in the nucleus

Electrons:

negatively charged
located around the nucleus

Atomic number (Z) = the number of protons in the nucleus of an atom.

(i apologize, i don't understand the last part...)

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Answer:

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A laser pulse with wavelength 525 nm contains 4.40 mj of energy. How many photons are in the laser pulse

Alexandra [31]

The laser pulse in this question has a wavelength of $\lambda=524 nm=525\times 10^{-9}m$ . To solve this problem, we first have to calculate the energy of a single photon in the laser pulse. The equation for calculating the energy of a single photon of an electromagnetic wave is $E=\frac{hc}{\lambda}$ where $c$ is the speed of light, $h$ is planks constant and $\lambda$ is the wave length of the photons.

For this problem, $c=3.0\times 10^8m/s$ , $h=6.63\times10^{-34}J.s$ and $\lambda=525\times 10^{-9}m$ . We use these values to calculate the energy of the photon as shown below,

$E=\frac{hc}{\lambda} \\E=\frac{(6.63\times 10^{32}Js)\times(3.0\times10^8m/s)}{525\times 10^{-9}m} \\E=3.79\times 10 ^{-19}J.$

Now that we know the energy for a single photon, we will divide the total energy given by the energy of one photon to get the number of photons in the pulse. The number of photons $n$ is calculated as shown below,