Hey can u guys help on this lab, I don't get it.
I have to figure out the: prediction, Analysis, and evaluation.
Problem: what is the molar enthalpy of ice?
mass of calorimeter: 3.76g
mass of calorimeter+ water: 103.26g
mass of calorimeter+ water+melted ice: 120.59g
initial temperature of ice:0.0 degress celcius
initial temperature of water:
32.4 degress celcius
final temp. of water: 15.6 degress celcius
The one thing I don't get is how to do the prediction and analysis. Can you help me figure out what the molar enthalpy of fusion of ice is? Thanks!
I assume you can calculate the mass of ice and mass of H2O from the data.
Plug all those values in and solve for delta H fusion. If you have trouble, post your work to the point where you are stuck and we can help you through.
I didn't define my terms. Tf is the final temperature and Ti is the initial temperature of the appropriate material (meltice ice or water).
I got the answer -338.79J/mol, would that be right? And are the units right?
(17.33*deltaHfusion) + (17.33*4.19*(15.6-0)) + (99.5*4.19*-16.8) = 0
(17.33*deltaHfusion) + (-5871.2458)=0
(-5871.2458)/ (17.33)= deltaHfusion
You have used 4.19 for the specific heat of water which has the units of J/g*C. The problem asks for the units per mole, not per gram. You may use your answer and multiply by the molar mass of H2O OR go back and substitute (I think it is 75.3 J/mol) for the 4.19 you used. I think I obtained about 6.08 kJ/mol or so and that is about what you have, too. My references list 4.184 and not 4.19 for the specific heat of water. At the least, I would use 4.18 and recalculate (then multiply by 18) or use 4.18 x 18.0 and get the answer in the units requested. I hope this helps.
I just looked at the problem you worked again and I think you have a sign wrong; i.e., you have 17.33X +(-5800something) = 0. When the 5800 something is carried to the other side it becomes a + number and the answer should be a positive number. And you added heat to the ice to melt it. At any rate, check your arithmetic and see if it doesn't come out a positive number. I meant to write that the first time and it slipped my mind.
THANK YOU! If I have any more questions I will ask.
oh i jus got it sry i am only in 8th..
Answer this Question
Hey guys, I just started a new topic in mathematics. I'm learning about how to use graphs to relate two quantities. I'm completely lost! Can someone help me with these questions? Thanks! ______________________________________________________________
- asked by Lupa
- 3,752 views
Hey guys! I was hoping someone could help me with the first two questions. I'm seriously brain dead right now and cannot figure these out. baylor.edu/content/services/document.php/110735.pdf 1) Suppose you see the trace to the right on your oscilloscope
- asked by skills
- 2,084 views
An Ap student got a lab report back with "-4.5 % error" written in red on it. He had found the boiling point of an unknown liquid to be 45 C. What is the correct boiling point of his unknown liquid? I know first I would write -4.5 % error = |4.5-x|/x x 100
- asked by Anonymous
- 1,799 views
Goodbye, Ms.Sue =(
I am so broken. This is everyone's fault (not the tutors). You guys told Ms. Sue to , and worst. you guys should feel ashamed. She tried helping you guys but you were bullying her. I'm so happy that Ms. Sue is in a better place where she doesn't have to
- asked by HomeworkStan
- 14,797 views
math grade 11
Determine the value of k for which the function f(x)= 4x^2- 3x+2kx+1 has two zeros. check these values in the original equation? i cant figure out the answer to it. It says in the book that it is k 3.5,but i don't know how they got it.
- asked by priya
- 8,937 views
Statistics / Math
If a student is chosen at random, find the probability of getting someone who is a man or a non-smoker. Round your answer to three decimal places. non regular heavy total man 135 64 5 204 women 187 21 9 217 total 322 85 14 421 Answer in decimal (round to
- asked by Sam
- 10,513 views
Calculate the theoretical amounts of 0.1000 M NaOH titrant used to titrate 0.8 and 0.9 g KHP Please show step by step solution , i need the correct significant figures and units to finish up the rest of the lab correctly i found the answer but for some
- asked by Jessy
- 1,166 views
Chemistry: Bunsen Burner Lab
Hi! I have recently completed a bunsen burner lab and need help with a few conclusion questions: 1) What kind(s) of energy is released by the reaction of fuel and air in this system? 2) Which part of the Bunsen flame is hottest? How do you know? ->I
- asked by Cicilia
- 1,065 views
. A student’s final grade in chemistry is determined by the following weights: Quizzes 5% Exam 1 20% Exam 2 20% Lab Reports 15% Research Paper 15% Final Exam 25% The student received the following grades: Lab reports: 75 80 70 75 85 69 90 75 Quizzes: 85
- asked by Leah brown
- 664 views
Ok so the question asks Below, draw Figure 0 and Figure 4 for the pattern below. Then describe Figure 100 in detail. So figure 1 a box with 2×2 with a tail of 2 boxes Then figure 2 Box 3×3 with a tail 4boxes Figure 3 Box 4×4 and tail 6 boxes . Please
- asked by Stacy
- 1,060 views
Hey guys, so today I have an assignment due. I finished the rest of the assignment but I was hoping someone could help me with this question. Drag each item to indicate whether it is a cause or effect of the Rio Grande water crisis.
- asked by Lupa
- 4,821 views
We performed a lab in class about a month ago concerning different types of equilibrium. One particular portion of the lab adding 5 mL of .3M HCl to 5 mL of .3 M Pb(NO3)2. After a precipitate finally formed, 8 mL of water was added to dissolve PbCl2. One
- asked by Kim
- 5,010 views
Hey guys, so I had my birthday week this week and I missed a bunch of days, I made all of them up except for this last one and I'm so tired please help. 1. How do you ask what someone is like in spanish? A)Como te llamas? B)Como es? C)Como soy? D)Como
- asked by OLD_E
- 3,606 views
1. Read the following sentences from "Lifeguard Rules!" “That’s it, Ira and Michael,” Francesca had said. "You guys don’t get a third warning. Go spend fifteen minutes out of the water. I’ll inform you when I’m ready to see you in the pool
- asked by Sandy East Ward
- 1,961 views
Hey could you help me? What is the sum? 7/4 + ( - 1/5 ) A:31/20 B:39/20 C:6/9 D:-7/20 Is it C?
- asked by Misty
- 1,456 views
hello*>* anyway this time it's for science thanks!
hey guys! here you go... are they right? Atmospheric Circulation Quick Check answers are coming just wait one sec.
- asked by Fist Name here...
- 1,145 views
The formula for the area A of the triangle is A=1/2BH, where B is the length of the base, and H is the height. Solve the equation for B. I don't know how I'm supposed to be able to figure this out?
- asked by lily
- 6,139 views
Math I REALLY NEED HELP!!!!!!!!!
A figure is dilated by a scale factor of 4. If the origin is the center of dilation, what are the coordinated in the original figure of a vertex located at (8,8) in the enlarged figure? A/(2,2) B/(4,4)
- asked by Sammy
- 3,606 views
Hey guys i have been at this for like 3 hours i need some sleep but i need to finish these two questions can y'all help Would you prefer to own a business in the German economy or British economy? Why? Compare and contrast the governments of Great Britain
- asked by U DONT KNOW ME
- 4,540 views
Hey just wondering if you think my answers right, 1)Biological safety cabinets are not required when working with containment level (blank) materials a) 1, b)2, c)3, d)4 - answer a? 2)Materials in Risk Group (blank) pose the least risk to the individual
- asked by Ethan
- 1,020 views