I believe it is either vaporization or boiling someone might need to correct me on it.
The relationship between energy and wavelength is shown by:
E = hc/wavelength
As we can see, there is an inverse relation between energy and the wavelength. The greater the energy, the shorter the wavelength. Among the mechanical waves listed, at the wavelength of 7 cm.
We know,

For given reaction, 

For , 2.41 moles of
:

We know :

Hence, this is the required solution.
Different forms of matter have different melting/boiling points. For example, at 100 degrees Celsius, H2O (water) will turn from lliquid to gas. But NaOH (table salt) doesn't even go from solid to liquid until some 800 degrees Celsius. So, in order to figure out which state matter is at 35 Celsius, you'd have to be more specific about what kind of matter...
Water freezes at 0°C, 32°F, and 273°K. The only temperature warmer than the freezing point is 1°C.