When a student dissolves 2.50 g of LiCl in 100.0 mL of water (100.0 g) the temperature rises from 24.0 oC to 29.11oC. What is ∆H in KJ/mol for the dissolution of LiCl in water? Make sure you include the correct sign for ∆H and units (with a space between number and unit)

Answers

Answer 1

Answer:

[tex]36.273\ \text{kJ/mol}[/tex]

Explanation:

m = Mass of LiCl = 2.5 g

M = Molar mass of LiCl = 42.394 g/mol

c = Specific heat of water = [tex]4.186\ \text{J/g}^{\circ}\text{C}[/tex]

[tex]\Delta T[/tex] = Change in temperature = [tex]29.11-24=5.11\ ^{\circ}\text{C}[/tex]

[tex]m_w[/tex] = Mass of water = [tex]\rho V=1\times 100=100\ \text{g}[/tex]

Number of moles

[tex]n=\dfrac{m}{M}\\\Rightarrow n=\dfrac{2.5}{42.394}\\\Rightarrow n=0.05897\ \text{mol}[/tex]

Heat is given by

[tex]Q=m_wc\Delta T\\\Rightarrow Q=100\times 4.186\times 5.11\\\Rightarrow Q=2139.046\ \text{J}[/tex]

Enthalpy is given by

[tex]\Delta H=\dfrac{Q}{n}\\\Rightarrow \Delta H=\dfrac{2139.046}{0.05897}\\\Rightarrow \Delta H=36273.46\ \text{J/mol}=36.273\ \text{kJ/mol}[/tex]

The enthalpy for the dissolution is [tex]36.273\ \text{kJ/mol}[/tex].


Related Questions

If we know the half life how could we determine what percentage of radioactive isotopes will be left after 4 half-lives?

Answers

Answer:

"After 1 half-life there will be 50% of the original isotope, and 50% of the decay product.

After 2 half-lives there will be 25% of the original isotope, and 75% of the decay product.

After 3 half-lives there will be 12.5% of the original isotope, and 87.5% of the decay product.

After 4 half-lives there will be 6.25% of the original isotope, and 93.75% of the decay product." -Stephen Frantz, Former Director of the Reed College Nuclear Reactor

Explanation:

A) Mention any two properties of an ideal fuel. (b) What is meant by calorific value? (c) 2kg of a fuel produces 48,000 KJ of heat energy and complete combustion. Calculate the calorific value of the fuel.

Answers

Answer and explanation:

A) An ideal fuel must:

- easy to transport and storage.

- have a high calorific value.

B) The calorific value for a fuel is the amount of heat - measured in Joules- which is produced during the complete combustion of the fuel. It is expressed in Joules per Kg of fuel (J/kg).

C) From the data:

mass of fuel = 2 kg

heat produced = 48,000 KJ

We calculate the calorific value by dividing the heat produced by the mass of fuel, as follows:

calorific value = heat produced/mass of fuel = (48,000 KJ)/(2 kg)= 24,000 kJ/kg

Since 1 KJ= 1000 J, we can express the calorific value in J/kg as follows:

24,000 kJ/kg x 1000 J/1 kJ = 2.4 x 10⁷ J/kg

what is the mass in grams of 0.00125 mole of sodium Na=23​

Answers

Answer:

0.03g

Explanation:

Given parameters:

Number of moles of Na = 0.00125mole

Unknown:

Mass in grams of Na = ?

Solution:

To find the mass of this substance, we simply multiply the number of moles with the given molar mass of Na.

 Mass of Na  = number of moles x molar mass

 Mass of Na  = 0.00125 x 23   = 0.03g

How many grams of C are required to react with 97.1 g of Fe2O3?

Answers

Answer:

21.9 g C

Explanation:

Fe₂O₃  +  3 C  ⇒  2 Fe  +  3 CO

This is your chemical equation.  

To find the grams of C required, first convert grams of Fe₂O₃ to moles using the molar mass (159.69 g/mol).  

(97.1 g)/(159.69 g/mol) = 0.608 mol Fe₂O₃

Then, use the mole ratio between Fe₂O₃ and C to convert moles of Fe₂O₃ to moles of C.  You can find the mole ratio by looking at the chemical equation.

(0.608 mol Fe₂O₃) × (3 mol Fe₂O₃/1 mol Fe₂O₃) = 1.824 mol C

You can then convert moles of C to grams using the molar mass (12.01 g/mol).

(1.824 mol) × (12.01 g/mol) = 21.9 g

A compound is made up of 30% nitrogen and 70% sulfur. the molar mass of a compound is 92 g/mol. What is the molecular formula of the compound?

Answers

Answer:

N2S2

I just took the quiz and it was right

Nitrogen and carbon can form ___ bonds in which six electrons ( three pairs ) are shared.
A. Single Covalent
B. Ionic
C. Hexadecimal
D. Triple covalent

Answers

i think the answer is D

What is the electric force acting between two charges of 0.0042 C and -0.0050 C that are 0.0030 m apart?

Answers

Answer: -2.1 x 10^10 N

Explanation:

Of the three states of water(ice,liquid, and water vapor), in which state are the intermolecular forces the strongest? In which state are they the weakest

Answers

The intermolecular forces are strongest when it’s solid because their molecules are close to each other. The state in which the intermolecular forces are the weakest is when its water vapor because the molecules are more free and it’s gas like

How do you think the atomic radii will change as electrons are added to a shell?

Answers

Answer:

As electrons are added to the valence shell, an extra proton (i.e fundamental, positively charged nuclear particle) is added to the element's nucleus. As electrons add and Z the atomic number increases 1 by 1, nuclear charge WINS, and electronic radii contract.

Explanation:

Hope this helps you

Crown me as brainliest:)

As electrons are added to the valence shell, an extra proton (i.e fundamental, positively charged nuclear particle) is added to the element's nucleus. As electrons add and Z the atomic number increases 1 by 1, nuclear charge WINS, and electronic radii contract.

what is the molar mass of ammonium sulfite

Answers

Answer: 116.15 g/mol

What pressure (in atm) does 3.54 moles of chlorine gas at 376 K exert on the walls of its 51.2 L container?

Answers

The answer to your question is P = 2.13 atm

Answer:

2.13 atm

Explanation:

Describe how the nervous system helps the boy detect the aroma coming from the pot on the stove.

Answers

Answer:

When a boy smells the aroma coming from the pot on the stove is actually detecting the chemicals coming from the air which comes from hot food that dissolves in the mucus present in the nasal cavity that carries tiny hairs made up of the nerve fibers that absorb these chemicals and excite or stimulate the olfactory receptors.

Various types of a distinct aroma or smell lead to a specific combination of the olfactory cells to make a specific smell. These combination patterns transported to the olfactory bulb along axons; a long extended neuron.

The sensory patterns or information encoding the smell of food present in the pot reaches the primary olfactory cortex in the brain, which is present on the anterior surface of the temporal lobe, and decodes accordingly.

Answer:You breath in what you smell and if it smells good or not you usely get up an see what is in the kitchen

Explanation:

saturn surface features

Answers

Answer:

Surface pressure: 140 kPa

Surface gravity: 10.44 m/s2 (34.3 ft/s2); 1.065 g

Surface area: : 4.27×1010 km2 (1.65×1010 sq mi

Average orbital speed: 9.68 km/s (6.01 miles/s)

Answer:craters

Explanation:

Can someone help me with this?

Answers

Answer:

b

Explanation:

it i b ur welcome

Answer: um sure so 2+4= 24 then 9+7=97

Explanation: bc if you have 2 and you have 4 and if you smash that together you get 24 and 9 and 4 smash that together and you get 94 see so easy

what is an autograph that transfers energy from the sun to make its own food?​

Answers

Answer:

Photoautotrophs

Explanation:

I think you mean "autotroph"

The answer is photoautotrophs. they use sunlight to make their food

Don't forget to rate the answer for others

What is the name for the compound S3N2

Answers

Answer:

Sulfur Nitride

Describe the structure of sodium metal?

Answers

Answer:

The body-centred cubic (bcc) structure is the most stable form for sodium metal at 298 K (25°C). Under normal conditions, all of the Group 1 (alakali metals) elements are based upon the bcc structure. The closest Na-Na separation is 372 pm implying a sodium metallic radius of 186 pm.

Explanation:

How many moles are in 35.0g of sodium (Na).

Answers

Answer:

2.5 I don't have a explanation

!PLEASE HELP ASAP!
How many grams of aluminum can be produced by decomposing 12.3 grams of aluminum
oxide?

Answers

102 grams per mole I think search it up on google


What is the molarity of a solution if 5 moles of solute are dissolved in 8 L of solvent.

Answers

Answer:

0.625mol/L

Explanation:

Given parameters:

Number of moles of solute = 5moles

Volume of solvent = 8L

Unknown:

Molarity = ?

Solution:

Molarity is the number of moles of solute per unit volume of solution. It is mathematically expressed as

  Molarity  = [tex]\frac{number of moles }{Volume}[/tex]  

  Molarity  = [tex]\frac{5}{8}[/tex]   = 0.625mol/L

In addition to Earth, which planet has evidence of water on the surface?
(one Answer)Thank you
Mars
Mercury
Neptune
Saturn

Answers

Answer:

mars

Explanation:

just googled it

In addition to Earth, mars  planet has evidence of water on the surface.

What are evidence of water?

Evidence proves that financing results  works Our strong evidence based on the  proves that more lives and real can be changed through access to affordable inventing  for water and sanitation.

Evidence of finding water on Mars first to be known  in 2000, with the appearance of gullies that suggested us about  a liquid origin. Their formation has been hotly in  debated over the ensuing years.

Therefore, addition to Earth, mars  planet has evidence of water on the surface.

Learn more about  evidence of water, here:

https://brainly.com/question/3406927

#SPJ6

Which type of energy produces almost no waste or pollution?

A: burning coal

B: nuclear energy

C: solar energy

Answers

Answer:

B: nuclear energy.

Explanation:

It is emission-free and it saves 2.4 billion tons of carbon emissions per year. Also, the level of hazard of nuclear waste does decrease during the time.

Hope that helps!

Magnesium will...

• Gain 2 electrons and become Mg2-

• Lose 2 electrons and become Mg2-

• Gain 2 electrons and become Mg2+

• Lose 2 electrons and become Mg2+

Answers

Answer:

D

Explanation:

magnesium always lose 2 electrons

At which point does a chemical reaction reach dynamic equilibrium?
A. When no further reaction occurs in either direction of the reaction
B. When the concentrations of reactants and products are different
O C. When reactants are decreasing rapidly and products are
increasing slowly
D. When the concentrations of reactants and products stay the same

Answers

Answer:

D. When the concentrations of reactants and products stay the same

Explanation:

[tex]\bigstar[/tex] Dynamic equilibrium is when rate of forward reaction is equal to the

   rate of backward reaction. The concentration of Product and Reactant

   are both same, no net change. Hence Option D is correct.

When the concentrations of reactants and products stay the same at this point a chemical reaction reach dynamic equilibrium.

Hence, Option (D) is correct answer.

What is a Chemical Reaction ?

A chemical reaction is a process in which chemical bonds between atoms to break and reorganize, to form other new substances.

What is Dynamic Equilibrium ?

Dynamic equilibrium occurs in reversible reactions when the number of particles becomes product is equal to number of particles becomes reactant. Chemical equilibrium is dynamic in nature.

Thus from the above conclusion we can say that When the concentrations of reactants and products stay the same at this point a chemical reaction reach dynamic equilibrium.

Hence, Option (D) is correct answer.

Learn more about the Dynamic Equilibrium here: https://brainly.com/question/1233365
#SPJ2


Explain the
purpose
of the heat exchanger in the nuclear power plant.

Answers

Answer:

yeah someone explain

Explanation:

tttttttttt%ttttttt

Answer:

A heat exchanger is device which is designed to transfer heat from one matter to another. In nuclear power plants, these heat exchangers are used to pass heat from primary system to the secondary system. In the process they produce steam from water, they are also called steam generators or pressurized water reactors.

A student found the percent composition of CO to be 50% C and 50% O. What did the student do Incorrectly? What is the percent composition of CO?

Answers

The percent is wrong it should be 42.88% carbon and 57.12% oxygen
It should be 42 carbon and 57 oxygen

what is the molar mass of iron (III) sulfate

Answers

Answer:

399.88 g/mol

Explanation:

Iron(III) sulfate, is the chemical compound with the formula Fe₂(SO₄)₃. Usually yellow, it is a salt and soluble in water. A variety of hydrates are also known. Solutions are used in dyeing as a mordant, and as a coagulant for industrial wastes.

Use the periodic table to select which type of bond is present and which of the listed properties is most likely for each substance.

A =
B =
Cu3Zn2
O2

Answers

Answer:

A :metallic

B :conducts electricity as a solid

C :covalent

D :does not conduct electricity

Explanation:

Answer:

A = ✔ metallic

B = ✔ conducts electricity as a solid

C = ✔ covalent

D = ✔ does not conduct electricity

Explanation:

edge 2023

All elements are unstable except the noble gases

True or False

Answers

Many elements only exist in an unstable or radioactive form. All non-natural or man-made elements are radioactive isotopes. Heavier isotopes tend to react more slowly than lighter isotopes of the same element. There are 254 known stable isotopes and 80 elements which have at least one stable isotope.

Answer:

True

Explanation:

Noble gases already have the maximum number of valence electrons they can hold so they are the only stable group

Which of the following is not a correct formula unit for a salt made from main group elements?
Ca0
AIFA
Al2O3
Ca3N2​

Answers

Answer:

The correct option is AlFA

Explanation:

There is no element in the periodic table with the symbol of A. Thus, the compound AlFA is wrong and cannot be a salt made from main group elements. CaO is calcium oxide, Al₂O₃ is aluminium oxide and Ca₃N₂ is calcium nitride - all are evidently made from elements from the main groups of the periodic table (except the AlFA)

Other Questions
This recipe normally creates 4 servings Can someone please modify this recipe so it creates 30 servings. I will give brainlist to whoever completes this1 cup fresh pineapple chunks1/2 cup cantaloupe or other melon chunks1 cup fresh strawberriesJuice of 2 oranges1 cup of cold water1 tablespoon honey The primary advantage of precision farming is that? If a water park sold 170 tickets and 30% of them were adult tickets, how many tickets did they sell that were not for adults? "We visited her this morning" they said.Reported speech During the prior fiscal year, Carla Vista Corp. signed a long-term noncancellable purchase commitment with its primary supplier to purchase $2.14 million of raw materials. Carla Vista paid the $2.14 million to acquire the raw materials when the raw materials were only worth $1.67 million. Assume that the purchase commitment was properly recorded. What is the journal entry to record the purchase Who is the current Chief Justice of the Supreme Court? Read the excerpt from "Object Lesson, Part 1.""Well, if it's a real live crime," he said, turning to Louise, "I don't imagine anyone wants to hear me ramble on about crimes that are dead and buried. In fact, I think it would be more interesting if I gave the class a demonstration of how a crime is actually solved. What do you think, Miss Carpenter?"Understanding leaped into her eyes, along with hope.This information supports the prediction that Ellery willwork to solve the classs crime.discuss crimes that happened in the past.feel nervous in front of the class.determine that the crime is not real. Which organelle in the table is correctly matched with its function?chloroplastcell wallcell membranevacuole Based on Egyptian Tombs: A Grave Matter, what will most likely occur if grave robbers find the tomb of Ramses VIII in the future? Compare and contrast Converse and Inverse. Explain. Societies that practice integration try to deal with multicultural populationsby:O A. forcing certain groups to leave the country or face consequences.O B. encouraging different groups to practice their unique beliefs.O c. pressuring minority groups to adopt the majority group's culture.O D. making sure minority groups are kept separate from the majority. What is the value of x? Please type your answer using numbers ONLY. NO SYMBOLS OR WORDS. Hint: Find the missing value of the bottom trianglefirst and look at the definition for vertical angles to help you find one ofthe missing angles on the top triangle.* Network Access Protection (NAP) analyses the ________ of a computer. do a analysis of lemon and herbs the person who does it gets 20 points What famous Government Building was burned by the British during the War of 1812The PentagonThe Treasury BuildingThe White HouseThe Capitol BuildingThe Lincoln Memorial EXPENSES: Camille has no more than $50.00 to spend each week for lunch and bus fare. Lunch costs $3.00 each day, and bus fare is $1.75 each ride. Write an inequality for this situation. Can Camille buy lunch 7 times and ride the bus 14 times in one week???? Ocean and freshwater contamination __________.A)does not affect marine lifeB)results from industrial activityC)is independent of human activityD)is only caused by flooding or surface runoffE)is not affected by agriculture Inside each of these organelles are stacks of The parts of the plant(angiosperms)involved in producing gametes(pollenand eggs) and seeds (fertilized eggs) *shoot systemreproductive systemPhloemxylem In a polar coordinate system, the midpoint of the line segment whose endpoints are $\left( 8, \frac{5 \pi}{12} \right)$ and $\left( 8, -\frac{3 \pi}{12} \right)$ is the point $(r, \theta).$ Enter $(r, \theta),$ where $r > 0$ and $0 \le \theta < 2 \pi.$