5. 3.4 kg of water is heated from 78 C to boiling and it is all turned to steam at

100C. How much heat did it take?

7.7 MJ

Explanation:

Let water specific heat be c = 0.004186 J/kgC and specific latent heat of vaporization be L = 2264705 J/kg

There would be 2 kinds of heat to achieve this:

- Heat to change water temperature from 78C to boiling point:

- Heat to turn liquid water into steam:

or 7.7 MJ

So the total heat it would take is

the body's situation won't change the forces are equal opposit and on the same body

what experimental evidence led scientists to change from the previous model to this one?

a few of the positive particles aimed at a gold foil seemed to bounce back.

the colors of light emitted from heated atoms had very specific energies.

experiments with water vapor showed that elements combine in specific proportions.

cathode rays were bent in the same way whenever a magnet was brought near them.