Help understanding what is being asked in 8.19

Moderators: Chem_Mod, Chem_Admin

Fenared Ortiz 3K
Posts: 37
Joined: Wed Nov 16, 2016 3:03 am

Help understanding what is being asked in 8.19

Postby Fenared Ortiz 3K » Tue Jan 16, 2018 11:04 pm

(a) Calculate the heat that must be supplied to a 500.0-g stainless steel vessel containing 400.0 g of water to raise its temperature from 22.0 C to the boiling point of water, 100.0 C.(b) What percentage of the heat is used to raise the temperature of the water? (c) Compare these answers with those of Exercise 8.17. (See Table 8.2.)

I am Having trouble understanding what is being asked in part a of the question and on how to approach it. I know that i have to use 0.51[J·( C) 1·g 1], but dont really know where and how

Hannah Chew 2A
Posts: 76
Joined: Fri Sep 29, 2017 7:05 am
Been upvoted: 2 times

Re: Help understanding what is being asked in 8.19

Postby Hannah Chew 2A » Tue Jan 16, 2018 11:34 pm

In part a, you need heat to increase the temperature of both the stainless steel in 8.20 (or copper in 8.19) and the water. Using the formula q = mass x specific heat capacity x temperature change, you would need to add q of water and q of stainless steel (or copper). These should be separate sums, meaning that you have to correctly correspond the temperature change to the matching mass and whatnot.

torieoishi1A
Posts: 32
Joined: Sat Jul 22, 2017 3:00 am

Re: Help understanding what is being asked in 8.19

Postby torieoishi1A » Thu Jan 18, 2018 1:59 pm

for part b, where they ask "what percentage of the heat is used to raise the temperature of the water?"
you take the amount of heat used to raise the temperature of the water and divide it by the total heat. Then multiply it be 100 to get the percent.
HEAT: q=mCdeltaT
((1.30 X 10^5J)/(1.45 X 10^5 J)) X 100
ANSWER: 90%


Return to “Heat Capacities, Calorimeters & Calorimetry Calculations”

Who is online

Users browsing this forum: No registered users and 1 guest