The value of specific heat for copper is 390 J/kg⋅°C, for aluminun is 900 J/kg⋅°C, and for water is 4186 J/kg⋅°C. What will be the equilibrium temperature when a 265 g block of copper at 235°C is placed in a 135g aluminum calorimeter cup containing 865 g of water at 14.0°C? Express your answer using three significant figures.

the equilibrium temperature Te = 19.9°C

Explanation:

Given;

specific heat for copper Cc is 390 J/kg⋅°C

for aluminun Ca is 900 J/kg⋅°C,

for water Cw is 4186 J/kg⋅°C

Mass of copper Mc= 265 g = 0.265kg

Temperature of copper Tc = 235°C

Mass of aluminium Ma = 135g = 0.135 kg

Temperature of aluminium Ta = 14.0°C

Mass of water Mw= 865 g = 0.865kg

Temperature of water Tw = 14.0°C

The equilibrium temperature can be derived by;

Te = (MaCaTa + McCcTc + MwCwTw)/(MaCa + McCc+ MwTw)

Substituting the values;

Te = ( 0.135×900×14 + 0.265×390×235 + 0.865×4186×14)/(0.135×900 + 0.265×390 + 0.865×4186)

Te = 19.939°C

Te = 19.9°C

you'd use the equation that establishes a relationship between  energy  and  wavelength, which looks like this

e=h⋅cλ, where

λ  - the wavelength of the photon; c  - the speed of light, usually given as  3⋅108m/s; h  -  planck's constant, equal to  6.626⋅10−34j s

plug the value you were given for the energy of the photon in the above equation to get the wavelength

e=h⋅cλ⇒λ=h⋅ce

λ=6.626⋅10−34js⋅3⋅108ms−1.257⋅10−24j=1.581⋅10−1m