Hello, my problem is as follows: " If 150 g of lead at 100°C were placed in a calorimeter with 50 g of water at 28.8°C and the resulting temperature of the mixture was 22°C, what are the values of q(lead), q(water), and q(cal)? (Knowing that the specific heat of water is 4.184 J/g °C and the...
I just have one quick question on using direct calorimeters on humans, and it might be a dumb question but its got me a bit confused.
From my understanding the calorimeter will measure the change in temperature of water from the heat that a person's body gives off.
I understand that when...
Homework Statement
10.11g of CaO (molar mass = 56.08 g / mol) is dropped into a styrofoam coffee cup containing 157.0 g of H2O at 25.0ºC. If the following reaction occurs, calculate the final temperature of the water assuming that the cup acts as a perfect insulator.
(Assume that the...
Homework Statement
in the reaction 10mL of 1M NaOH + 5mL of 1M HCl (adiabatic)
given change in temp=2.1°C (temp initial is the temp of NaOH, temp final is acquired after the addition of HCl)
find: qrxn, qcal, Ccal
Homework Equations
qrxn = -qca
Ccal = qcal/∆T
The Attempt at a...
Homework Statement
When using the equation Q=mcΔT for the substance being tested is it the mass of the substance or the mass of the substance + mass of water.
Homework Equations
The Attempt at a Solution
So when I solve calorimetry problems, I usually find Qwater. Then I set...
Homework Statement
A copper sample whose mass mc is 75 g is heated in a laboratory oven to a temperature of 312 degrees Celsius. The copper is then dropped into a glass beaker containing mass mw = 220 g of water. The effective heat capacity of the beaker is 190 J/K. The initial temperature of...
Homework Statement
The reaction of 0.050 g of solid Mg with 100.0 mL of 1.00M aqueous HCl solution is carried out in a coffe-cup calorimeter. The temperature of the solution increases from 22.21 degrees Celsius to 24.46 degrees Celsius. How much heat is produced by the reaction?
Homework...
My Physics III class is going through basic Thermodynamics and I have hit a bit of an impasse. This is relatively simple stuff, but for some reason, I cannot get this problem right. I've worked on it to the point of confusing myself pretty thoroughly. I would really appreciate some direction...
Homework Statement
An alcohol rub can rapidly reduce an elevated body temperature in a patient. The heat energy lost by the person is due to the evaporation of alcohol. Find the number of grams of alcohol that must be evaporated from the surface of a 75 kg person to reduce the body...
Homework Statement
A 125-g stainless steel ball bearing at 545C⁰ (steel has a specific heat capacity of 0.50J g⁻¹C⁻¹) is dropped into 80mL of water at 27.5C⁰ in an open Styrofoam cup. As a result, the water is brought to a boil when the temperature reaches 100.0C⁰.
What mass of water...
Homework Statement
So basically our teacher gave us a bunch of materials and told us to conduct an experiment including the notes on change of heat we took earlier in the week. This is what my group conducted.
We acquired 125 mL of water that started at 21 degrees celsius. We then heated...
The problem:
On a hot summer day, you decide to make some iced tea. First, you brew 1.50 L of hot tea and leave it to steep until it has reached a temperature of T_tea = 75.0 C. You then add 0.975 kg of ice taken from the freezer at a temperature of T_ice = 0 C. By the time the mix reaches...
Homework Statement
Sodium metal reacts with water to produce hydrogen gas and sodium hydroxide
according to the equation:
2 Na(s) + 2 H2O(l) ? 2 NaOH(aq) + H2(g)
When 0.030 mol of Na is added to water, the temperature of the calorimeter rises
from 25.00C to 37.90C. If the heat...
Homework Statement
A 53.5 g ice cube, initially at 0°C, is dropped into a Styrofoam cup containing 369 g of water, initially at 21.4°C. What is the final temperature of the water, if no heat is transferred to the Styrofoam or the surroundings?
Homework Equations
Lf*m + Mc Delta T = MC Delta...
Homework Statement
A 300-g aluminum vessel contains 200 g of water at 10 0C.
100 g of steam at 1000C is poured into the container, what is the final equilibrium temperature of the system?
Homework Equations
Given that the:
specific heat of Al = 910 J/kg 0C.
specific heat of water =...
Homework Statement
A 300 g piece of aluminum at a temperature of 75 degrees C is dropped into a calorimeter containing 400 mL of water at 5 degrees C. What is the final temperature? The C Al = 0.9 J/g degrees C.
Homework Equations
q = mcdeltat
The Attempt at a Solution
I have no...
Homework Statement
Simple Coffee cup Calorimetry.
Heat capacity of calorimeter was measured experimentally.
Mg ribbons dissolved in aq HCl in coffee cup calorimeter and measurements taken.
MgO was then dissolved in another setup of identical calorimeter and measurements taken.
My...
Homework Statement
What mass of ice at -10.0 degrees celsius is needed to cool a whale's water tank, holding 1.20 x 10^3 m^3 of water, from 20.0 degrees down to a more comfortable 10 degrees.
Homework Equations
Q = mc *delta T
Q = mL
The Attempt at a Solution
i'm trying to...
Homework Statement
A copper container of mass 0.080kg and specific heat of 387Jkg-1K-1 contains 0.30kg of water and 0.040kg of ice at 0degrees. Steam at 100 degrees is passed into the water and its temperature stabilizes at 20.0degrees. Find the mass of the water left in the container...
Homework Statement
A quantity of 2.00x10^2 mL of .862 M HCl is mixed with 2.00x10^2 mL of .431 M Ba(OH)2 in a constant-pressure calorimeter of negligible heat capacity. The initial temperature of the HCl and Ba(OH)2 solutions is the same at 20.48 C.
For the process
H+(aq) + OH-(aq) -->...
Hi, here is a basic summary of what we did in a lab; there were 3 reactions:
The procedure:
Reaction 1: Solid sodium hydroxide dissolves in water to form an aqueous solution of ions.
NaOH(s)-> Na+(aq) + OH-(aq) ΔH1=-34.121kJ
Reaction 2: Solid sodium hydroxide reacts with an aqueous...
Homework Statement
A block of ice at 0C is added to a 150g aluminum calorimeter cup which holds 210g of water at 12C. If all but 2.0 g of ice melt, what was the original mass of the block of ice
Homework Equations
heat gained by ice = heat lost by water + heat lost by calorimeter...
Homework Statement
A student attempts to identify a metal by measuring its specific heat capacity. 100g of the metal is heated to 75°C and then transferred to a 70g copper calorimeter containing 200g of water at 20°C. The temperature of the final mixture is 25°C.
Homework Equations...
Hi everyone,
I'm taking a first year physics course and our upcoming lab is an experiment to determine the Heat of fusion for ice. There are a few questions that I have.
Firstly the overall equation is given as Lfm + cm (T2 - 0) = cmw (T1 - T2) + cAmA (T1 - T2) + q
Where:
m is the...
Homework Statement
You cool a 90.0 g slug of red-hot iron (temperature 745 C) by dropping it into an insulated cup of negligible mass containing 85.0 g of water at 20.0 C. Assume no heat exchange with the surroundings.
What is the final temperature of the water?
Homework Equations...
I have a question that i cannot get an answer too.
AgNO3 (s) ---> Ag (aq) + NO3 (aq)
THESE ARE THE GIVEN:
ΔH=0.908 kJ
c(Cu)=0.3900 J/g ͦC
--------------------------------------
Calculate the final temperature of a solution if 25.00g of pure AgNO3 is dissolved in 250.0mL of water...
Homework Statement
Calculate the heat absorbed by the water in the calorimeter and the heat released by 1,0g of burning ethanol. Then, calculate the molar heat of combustion (kJ/mol) of the ethanol.
The calorimeter used was very makeshift: ethanol in an alcohol burner was lit under a can...
Homework Statement
A 10 gram quantity of water at 25 degrees Celsius is poured onto a 400 gram block of ice which is at -10 degrees Celsius. Assume that all the heat is contained within these two objects. Determine the final equilibrium temperature.
Specific heat of water is 4186 J/kgK...
This is a conceptual question...hope you guys can explain the answers that the book gives! Its frustrating me to no end. This is actually a problem in the Enthalpy chapter, calorimetry section of section exercises of the Olmsted and Williams chemistry textbook, 3rd ed.
Any help would be...
A 25.0g ice cube at its melting point is added to a calorimeter water at 25.4ºC. When thermal equilibrium is reached, the final temperature of the mixture is at 15.0ºC. The original volume of water in the calorimeter was?
This is all the data given.
A. 93.4mL
B. 136mL
C. 209mL
D. 228mL...
Homework Statement
For the reaction 2H2O(l) -> 2H2(g)+O2(g) delta H = +571.5 kJ
If the reaction is carried out in an insulated chamber what effect would the reaction have on the temperature in the chamber? Why?
The attempt at a solution
I can't seem to get my head around this one. I...
Homework Statement
In order to take a nice warm bath, you mix 60 litres of hot water at 55◦C with 30 litres of
cold water at 10◦C. How much new entropy have you created by mixing the water?
Homework Equations
Q=mc\Delta{T}
dS=dQ/T
The Attempt at a Solution
Greetings!
I am...
PRoblem statement-
The specific heat of silver is 0.235J/gC and the specific heat of water is 4.184J/gC. A piece of silver at 94.31C was dropped into a constant pressure calorimeter containing 148g of water at 24.08C. The final temperature of the water and silver was 25.39C. Assuming that the...
Homework Statement
what mass of water could be warmed from 23.8 C to 46.3 C by a 100 g metal pellet at
116 C
Homework Equations
The Attempt at a Solution
well i know the formula qsurr=ms\DeltaT
so qwater=ms\DeltaT
but then how do i work my way around when the heat capacity isn't also given...
to the admin. pls. don't delete this i figure it be easier to understand this if it's set up this way because its a prelab.thanks
I. 89.7716 g of metal were heated to 99.8 °C and poured into a calorimeter containing 46.20 g of water at 28.45 °C.
After stirring, the temperature of the water...
Homework Statement
A student mixed 200.00ml of 1.5mol/L sulphuric acid with 400.00ml of 1.5mol/L sodium hydroxide. Both solutions were at 19.67 degrees celsius initially and the highest temperature reached by the reaction mixture was 34.06 degrees celsius. Calculate the molar enthalpy of...
Hi there,
I currently have an assignment on calorimetry. I chose to burn different kinds of potato chips and measure the energy that they produce. I am now in the process of writing up my report and I am struggling to understand the respiration reaction.
The most common type of...
If anyone could possibly help me and explain how to do this problem it would be much appreciated..
A 50g copper mass is heated by placing it in boiling water. It is then placed in a beaker containing 250g of an unknown liquid at 20C. The final temperature of the weight and liquid is found to...
The question is:
An insulated beaker with negligible mass contains liquid water with a mass of 0.225 kg and a temperature of 75.8 C.
How much ice at a temperature of -23.6 C must be dropped into the water so that the final temperature of the system will be 31.0 C?
Take the specific heat of...
I need to determine the concentration of 100cm3 of aqueous sodium hydroxide solution (approximately to 2 mol dm-3) using 200cm3 of sulphuric acid by calorimetry (Enthalpy of neutralisation).
I am using E=mct. As its an exothermic reaction i will be finding the temperature difference. From...
Hey guys, I'm having a real tough time with this question:
A 30.14-g stainless steel ball bearing at 117.82 degrees C is place in a constant pressure calorimeter containing 120.0 mL of water at 18.44 degrees C. If the specific heat of the ball bearing is 0.474 J/g x C, calculate the final...
I am doing a lab in which I have to come up with my own procedure. The lab involves putting a hot metal into water, then using calorimetry calculations to find the mass of the metal. (The metal is hotter than the water).
What I don't understand is how you know when to stop taking the final...
[SOLVED] Specific heat capacity (Calorimetry)
Homework Statement
When a driver brakes an automobile, friction between the brake disks and the brake pads converts part of the car's translational kinetic energy to internal energy. If a 1500 kg automobile traveling at 32 m/s comes to a halt...
Can anybody help me out with this problem please. I'm not sure that I'm doing it right.
A 1.841 g sample of butanoic acid, C4H8O2 (88.11 g/mol) was burned in a bomb calorimeter with excess oxygen. The temperature of the calorimeter and the water before combustion was 17.26 degrees C; after...
Is there anybody that can tell me if I'm doing this question right?
Metallic Ca reacts with hydrochloric acid according to the following equation:
Ca(s) + 2 HCl(aq) ---> 2 CaCl2 (aq) + H2(g)
The enthalpy change associated with this reaction can be determined with an ice calorimeter. If...
can anybody here help me out with this problem?
A quantity of 4.00 x 10^2 mL of 0.600 M HNO3 is mixed with 4.00 x 10^2 mL of 0.300 M Ba(OH)2 in a constant-pressure calorimeter of negligible heat capacity. The initial temperature of both solutions is the same at 18.46 degrees C. What is the...
This is a general question... when given a calorimetry problem that states the molarity of the solution, the volume, and the density, why must the density be used in order to find the mass? Why can't the molarity be used (you can find moles and then use molar mass to convert to grams)?
Hi, here is the problem that I'm having trouble with.
It is desired to cool iron parts from 600°F to 200°F by dropping them into water that is initially at 55°F. Assuming that all the heat from the iron is transferred to the water and that none of the water evaporates, how many kilograms of...
Calorimetry...Please HELP! Test On Wednesday!
Homework Statement
500g of soda in a 90g glass at 20 deg C, an ice cube of mass 100g is added. Will all of the ice melt? What is Tf?
Tice = -20 deg C
Homework Equations
calorimeter - glass
What loses heat - glass and soda
What gains heat -...