# Lauren

posted by .

The specific heat of water is at 4.184J/g * degree C. How much heat is evolved, or absorbed, when the temperature of 9.00 mol of liquid water cools from 38 degrees C to 28 degrees C?

How do I start this problem

• Lauren -

q = mass x specific heat x delta T.
You will need to change the mols of water to grams.

• Lauren -

wouldnt it be 4.184J/g * degrees C

so 4.184 J/ 162 g H2O * 10 degrees C = ?

• Lauren -

mols = grams x molar mass
9.00 mols H2O x (18.015 g/mol) = ?? g H2O
q = g H2O x 4.184 J/g*C x delta T
and delta T = (Tfinal - Tinitial) = (38-28) = -10.
The answer will be a negative number which means that heat is evolved (and not absorbed).

• Lauren -

-6783.72 J

• Lauren -

ok. Actually, if we round the numbers, the last 2 should be a 3. However, if you are concerned about the number of significant figures, the 9.00 limits them to three; therefore, the -6383.73 J would be written as -6.38 x 10^3 Joules.

## Similar Questions

1. ### Physics

Spent steam from an electric generating plant leaves the turbines at 120.0 degrees Celsius and is cooled to 90.0 degrees Celsuius liquid water by water from a cooling tower in a heat exchanger. How much heat is removed by the cooling …
2. ### Chemistry

A quantity of ice at 0.0 degrees C was added to 33.6 of water at 21.0 degree C to give water at 0.0 degrees C. How much ice was added?
3. ### Chemistry

if the temperature of a 500.0g sample of liquid water is raised to 2.00c how much heat is absorbed by the water?
4. ### Chemistry

80.0 mL of water is initially at room temperature (22degrees C). A chilled steel rod at 2 degrees C is placed in the water. If the final temperature of the system is 21.2 degrees C, what is the mass of the steel bar?
5. ### chemistry

given the following info for water molar heat of specific heat capacity of liquid water 4.18 j/g degrees calculate the total quanity of heat evolved when 10.0g of steam is condensed,cooled,and frozen to ice at -50 degrees
6. ### chemistry

a 100.00 mL sample of water has an initial temperature of 20.0 degrees C. The water is heated, and after 5 minutes its temperature is 50 degrees C. approximately how much energy was absorbed by the water?
7. ### Science

1. How much heat energy is lost by 3 kg of water when it cools from 80 degrees C to 10 degrees C?
8. ### chemistry

A 94.7 g sample of silver (s= 0.237 J/(g x Degree C)), initially at 348.25 Degrees C , is added to an insulated vessel containing 143.6 g of water (s=4.18 J/(g x Degree C)), initially at 13.97 Degrees C. At equilibrium, the finial …
9. ### chemistry

If the temperature of a 500.0-g sample of liquid water is raised 2.00c how much heat is absorbed by the water?
10. ### Chemistry

Heat from burning a fuel is absorbed by a copper calorimeter. The calorimeter has a mass of 81.34 g and contains 200.0 g of water initially at 21 degrees Celsius. a) How much heat was absorbed by the calorimeter and the water if the …

More Similar Questions