Posted by Sarah on Monday, January 23, 2012 at 11:46pm.
A certain microwave oven delivers 633 watts (J/s) of power to a coffee cup containing 53.1 g of water at 25°C. If the wavelength of microwaves in the oven is 9.75 cm, how long does it take, and how many photons must be absorbed, to make the water boil? The specific heat capacity of water is 4.18 J/°C·g. Assume only the water absorbs the energy of the microwave.
___________ s
____________ photons

Chemistry  DrBob222, Tuesday, January 24, 2012 at 12:18am
How many J needed to raise T from 25C to 100 C? That is mass H2O x specific heat H2O x delta T = about 16,000 J but you need to get a more accurate number.
How much energy is available for a photon?
That is E = hc/wavelength =
6.626E34*3E8/0.0975m = about 2E24 J/photon.
2E24 J/photon x # photons = 16,000
Solve for # photons.
633 J/s x # seconds = 16,000
Solve for # seconds.
Check my work. It's getting late.
Answer This Question
Related Questions
 chemistry  A certain microwave oven delivers 800. watts (J/s) of power to a ...
 Chemistry  A particular microwave oven delivers 800 watts. (A watt is a unit of...
 physics....  Suppose that the inside length of a microwave oven is 30 cm. If ...
 AP Chemistry  Microwave ovens emit microwave radiation that is absorbed by ...
 chemistry  Your 1.1 cubic foot GE microwave oven generates 1100 watts of ...
 chemistry  A microwave oven heats by radiating food with microwave radiation ...
 chemistry  A microwave oven heats by radiating food with microwave radiation ...
 chemistry  A microwave oven heats by radiating food with microwave radiation, ...
 Chemistry  microwave ovens work by irradiating food with microwaves, which is ...
 Physics  An ice cube is placed in a microwave oven. Suppose the oven delivers ...
More Related Questions