1) here has been a great deal of controversy over whether cell phones cause brain cancer due to the emission of high energy waves near the head. The data on this is still being discussed (see NY Times article if you want more information) but we can do a simple calculation. Many cancers are caused by defects that develop in cellular DNA as a result of a bonds breaking in response to an external energy source (UV light, etc.). The average bond strength for a C-C bond is about 350 kJ/mol, so it would take at least this much energy to break a mole of these bonds.

Question

1) here has been a great deal of controversy over whether cell phones cause brain cancer due to the emission of high energy waves near the head. The data on this is still being discussed (see NY Times article if you want more information) but we can do a simple calculation. Many cancers are caused by defects that develop in cellular DNA as a result of a bonds breaking in response to an external energy source (UV light, etc.). The average bond strength for a C-C bond is about 350 kJ/mol, so it would take at least this much energy to break a mole of these bonds.

How much energy would it take to break just one C-C bond? Report your answer in Joules

2)The non-ionizing radiation emitted by cell phones has wavelengths in the radio range of the electromagnetic spectrum. Cell phones are on the upper end of the radio wavelengths, usually from 0.10 meters up to 1.0 meters. If your phone emits radiation at a wavelength of 0.26 meters, how much energy is the phone emitting?

Recall that Planck's constant = 6.63 10-34Js,
and the speed of light = 3.00 108 m/s2

Answer 1

1) To calculate the energy required to break a C-C bond, we can use the average bond strength of 350 kJ/mol. We need to convert this value to joules per mole since the energy is typically reported using joules.

First, we need to convert kJ to J by multiplying the value by 1000:
350 kJ/mol * 1000 J/kJ = 350,000 J/mol

Now, to find the energy required to break just one C-C bond, we divide this value by Avogadro's number (6.02 x 10^23/mol):
350,000 J/mol / 6.02 x 10^23/mol ≈ 5.81 x 10^-19 J/bond

Therefore, it would take approximately 5.81 x 10^-19 joules to break just one C-C bond.

2) To calculate the energy emitted by the cell phone, we can use the formula E = hc/λ, where E is the energy, h is Planck's constant (6.63 x 10^-34 J·s), c is the speed of light (3.00 x 10^8 m/s), and λ is the wavelength of the radiation.

Plugging in the values:
E = (6.63 x 10^-34 J·s)(3.00 x 10^8 m/s) / 0.26 m

E ≈ 2.41 x 10^-24 J

Therefore, the phone emits approximately 2.41 x 10^-24 joules of energy.