# college-- chemistry

posted by .

I am having a problem with this problem from my homework. I need some help on this problem.

Microwave ovens work by irradiating food with microwave radiation, which is absorbed and converted into heat. Assume radiation with wavelength=15.0cm is used and that all the energy is converted to heat. How many photons are necessary to raise the temperature of a 350mL quantity of water from 20.0 degree C to 95.0 degree C?

• college-- chemistry -

(a)
The energy of a photon is given by:
E = hf
h = Planck's constant (look it up)
f = frequency = speed of light / wavelength
f = (3.00x10^8 m/s) / (0.15m) = _____?
E = ______?
(b)
∆T = T2 - T1 = ____?
Heat needed = (4.18 J/g.C)(grams H2O)(∆T)
Heat = _________?
(c)
Divide the heat calculated in part (b) by the energy per photon calculated in part (a)

## Similar Questions

1. ### CHEMISTRY

I don't even understand how this question works. How do I solve it?
2. ### chemistry 121

Microwave ovens use microwave radiation to heat food. The microwaves are absorbed by moisture in the food, which is transferred to other components of the food. As the water becomes hotter, so does the food. Suppose that the microwave …
3. ### chemistry 121

Microwave ovens use microwave radiation to heat food. The microwaves are absorbed by moisture in the food, which is transferred to other components of the food. As the water becomes hotter, so does the food. Suppose that the microwave …
4. ### More chemistry

Hey jiskha. Microwave ovens emit microwave radiation that is absorbed by water. The absorbed radiation is converted to heat that is transferred to other components of the food. Suppose that the microwave radiation has a wavelength …
5. ### Chemistry!

Hey jiskha. Microwave ovens emit microwave radiation that is absorbed by water. The absorbed radiation is converted to heat that is transferred to other components of the food. Suppose that the microwave radiation has a wavelength …
6. ### chemistry

A microwave oven heats by radiating food with microwave radiation which is absorbed by the food and converted to heat. Suppose an oven's radiation wavelength is 12.5 cm. A container with 0.250 liter of water was placed in the oven …
7. ### chemistry

A microwave oven heats by radiating food with microwave radiation which is absorbed by the food and converted to heat. Suppose an oven's radiation wavelength is 12.5 cm. A container with 0.250 liter of water was placed in the oven …
8. ### Chemistry

microwave ovens work by irradiating food with microwaves, which is absorbed by the water molecules in the food and is converted into heat. Assuming that microwave ovens emit radiation with a wavelength of 12.2cm, calculate how many …
9. ### Chemistry

Microwaves are used to heat food in microwave ovens. The microwave radiation is absorbed by moisture in the food. This heats the water, and as the water becomes hot, so does the food. How many photons having a wavelength of 3.00 mm …
10. ### Chemistry

Microwave ovens heat food by creating microwave electromagnetic radiation that is absorbed by water molecules in the food. Any material that does not have water in it will not absorb the radiation and will not get hot. Metals reflect …

More Similar Questions