[Scitechian]

I'm doing a review for my Chem 2 test tomorrow and i can't seem to answer the following questions. nehelp on any of these three would be great.
Thanks in advance!!
 



43. A 150.0 –g sample of a metal at 75.0 deg C  is added to 150.0 g of h2O at 15. deg C. The temperature of the water rises to 18.3 C. Calculate the specific heat capacity of the metal, assuming that all the heat lost by the metal is gained by the water.




47. Consider the dissolution of CaCl2:

   CaCl2 (s)  Ca ^(2+) (aq) + 2 Cl ^ (-1)  (aq)      deltaH= -81.5 kJ

An 11.0 g sample of the CaCl2 is dissolved in 125 g of water, with both substances at 25. C. Calculate the final temperature of the solution assuming no heat lost to the surrounding and assuming the solution has a specific capacity of 4.18 J/deg C x g.



49. Camphor (C10 H16 O) has an energy of combustion of -5903.6 kJ/mol. When a sample of camphor with mass .1204 g is burned in a bomb calorimeter, the temperature increases by 2.28 C. Calculate the heat capacity of the calorimeter.

[Padfoot]

43. A 150.0 –g sample of a metal at 75.0 deg C  is added to 150.0 g of h2O at 15. deg C. The temperature of the water rises to 18.3 C. Calculate the specific heat capacity of the metal, assuming that all the heat lost by the metal is gained by the water.

Given equilibruim temp of water, what is that of metal?
Rearrange  q=mCdeltaT so you can solve for C.

47. Consider the dissolution of CaCl2:

   CaCl2 (s)  Ca ^(2+) (aq) + 2 Cl ^ (-1)  (aq)      deltaH= -81.5 kJ

An 11.0 g sample of the CaCl2 is dissolved in 125 g of water, with both substances at 25. C. Calculate the final temperature of the solution assuming no heat lost to the surrounding and assuming the solution has a specific capacity of 4.18 J/deg C x g.

How much heat released in the dissolution of your 11g?
For temp change, consider above value, specific heat and total mass.

49. Camphor (C10 H16 O) has an energy of combustion of -5903.6 kJ/mol. When a sample of camphor with mass .1204 g is burned in a bomb calorimeter, the temperature increases by 2.28 C. Calculate the heat capacity of the calorimeter.

0.1204g is how many mol?
Given deltaH (kJ/mol), what was heat released?
Heat capacity is J/K (or J/C).

I'm doing a review for my Chem 2 test tomorrow

Good Luck!