Benzene is a starting material in the synthesis of nylon fibers and polystyrene (styrofoam). its specific heat capacity is 1.74 j/g·°c. if 16.7 kj of energy is absorbed by a 225-g sample of benzene at 20.0°c, what is its final temperature?

The final temperature of the sample is 62.66°C

Explanation:

To calculate the amount of heat absorbed, we use the equation:

where,

Q = heat absorbed = 16.7 kJ = 16700 J   (Conversion factor:  1 kJ = 1000 J)

m = Mass of the sample = 225 g

c = specific heat capacity of sample =

= change in temperature =

Putting values in above equation, we get:

Hence, the final temperature of the sample is 62.66°C

"you start with 15.67 g mgco3-xh2o, when heated and all the water is removed, you are left with 7.58 g mgco3 only.

therefore, you had 15.67 - 7.58 = 8.09g h2o  

moles of each :

7.58g mgco3 = ? moles = 7.58g / 83.4g/mole = 0.09moles  

8 09g h2o = ? moles = 8.09g / 18g/mole = 0.44moles  

molar ratio between the two by dividing both numbers by the smallest number :

0.09 / 0.09 = 1  

0.44 / 0.09 = 4.8  

mgco3-5h2o"