A sample of 10.6 g of KNO3 was dissolved in 251.0 g of water at 25 oC in a calorimeter. The final temperature of the solution was 21.5 oC. What is the molar heat of solution of KNO3

Answers

Answer 1

Answer:

36.55kJ/mol

Explanation:

The heat of solution is the change in heat when the KNO3 dissolves in water:

KNO3(aq) → K+(aq) + NO3-(aq)

As the temperature decreases, the reaction is endothermic and the molar heat of solution is positive.

To solve the molar heat we need to find the moles of KNO3 dissolved and the change in heat as follows:

Moles KNO3 -Molar mass: 101.1032g/mol-

10.6g * (1mol/101.1032g) = 0.1048 moles KNO3

Change in heat:

q = m*S*ΔT

Where q is heat in J,

m is the mass of the solution: 10.6g + 251.0g = 261.6g

S is specififc heat of solution: 4.184J/g°C -Assuming is the same than pure water-

And ΔT is change in temperature: 25°C - 21.5°C = 3.5°C

q = 261.6g*4.184J/g°C*3.5°C

q = 3830.87J

Molar heat of solution:

3830.87J/0.1048 moles KNO3 =

36554J/mol =

36.55kJ/mol


Related Questions

What is the source of energy stored by ATP in cells?
Answers

A.
oxidation of biological compounds

B.
reduction of biological compounds

C.
synthesis of biological compounds

D.
polymerization of biological compounds

Answers

Answer:

I think C (synthesis of biological compounds

Explanation:

have a nice day

Identify the compound with ionic bonds.
CO
H2O
Ne
KCl
O2

Answers

Answer:

CO =Coordinate Covalent Bond ,H2O = Water , NE= Nickel or Neon ,KCL=Potassium Chloride and O2 = Water

Explanation:

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A student isolated an unknown organic compound through extraction. The student measures the melting point and fins it to be 115-122 C. The student looks through the list of possible strucures and decides the comound is most likely 2-napthol. Do you believe this choice is correct?

Answers

Hope this helps!

https://www.chegg.com/homework-help/questions-and-answers/student-isolated-unknown-organic-compound-extraction-student-measures-melting-point-finds--q77093697

The first step of electrophilic aromatic substitution involves the formation of the arenium ion intermediate.

a. True
b. Fasle

Answers

Answer:

True

Explanation:

Aromatic compounds undergo substitution rather than addition reactions because the aromatic structure is maintained.

Electrophilic aromatic substitution begins with attack of the electrophile on the aromatic ring to yield a delocalized intermediate called the arenium intermediate. Loss of hydrogen from this intermediate yields the final product.

What is the formula for the compound made from mercury (II) and the nitrate ion.

Answers

Answer:

Hg(NO3)2

Explanation:

Hg occurs both as Hg(I) and Hg(II) but nitrate is -1, not -2 We NORMALLY use the smallest set of subscripts but in the case of Hg(I) compounds, most of them are dimeric. Hg2Cl2, Hg2(NO3)2, etc. Note that there also is a mercury(II) nitrate; i.e., Hg(NO3)2. Therefore, although the empirical formula for mercury(I) nitrate is HgNO3, the molecular formula is Hg2(NO3)2 anf I was always encouraged to write the molecular formula instead of the empirical formula.

Hope this helps! Feel free to shoot me any questions <3

· Acids are not safe to be used, but our stomach secretes hydrochloric acid. What would happen if the stomach does not carry out this task?​ Mark them brainlist

Answers

If your stomach does not create HCL(hydrochloric acid)then these will happen
1. Instead of your food be digested it will stay there and the bacteria’s will multiply there

A sample of oxygen gas at a pressure of 1.19 atm and a temperature of 24.4 °C, occupies a volume of 18.7 liters. If the gas is allowed to expand at constant temperature to a volume of 29.4 liters, the pressure of the gas sample will be ______ atm.

Answers

Answer:

[tex]\boxed {\boxed {\sf 0.757 \ atm}}[/tex]

Explanation:

We are asked to find the pressure of a gas given a change in volume. Since the temperature remains constant, we are only concerned with volume and pressure. We will use Boyle's Law, which states the volume is inversely proportional to the pressure. The formula for this law is:

[tex]P_1V_1= P_2V_2[/tex]

Initially, the oxygen gas occupies a volume of 18.7 liters at a pressure of 1.19 atmospheres.

[tex]1.19 \ atm * 18.7 \ L = P_2V_2[/tex]

The gas expands to a volume of 29.4 liters, but the pressure is unknown.

[tex]1.19 \ atm * 18.7 \ L = P_2 * 29.4 \ L[/tex]

We are solving for the new pressure, so we must isolate the variable [tex]P_2[/tex]. It is being multiplied by 29.4 liters. The inverse operation of multiplication is division. Divide both sides of the equation by 29.4 L.

[tex]\frac {1.19 \ atm * 18.7 \ L}{29.4 \ L} =\frac{ P_2 * 29.4 \ L}{29.4 \ L}[/tex]

[tex]\frac {1.19 \ atm * 18.7 \ L}{29.4 \ L} =P_2[/tex]

The units of liters cancel.

[tex]\frac {1.19 \ atm * 18.7 }{29.4 } =P_2[/tex]

[tex]\frac {22.253}{29.4 } \ atm = P_2[/tex]

[tex]0.7569047619 \ atm =P_2[/tex]

The original measurements all have 3 significant figures, so our answer must have the same. For the number we calculated, that is the thousandth place. The 9 in the ten-thousandth place to the right of this place tells us to round the 6 up to a 7.

[tex]0.757 \ atm \approx P_2[/tex]

The pressure of the gas sample is approximately 0.757 atmospheres.

Answer:

According to Boyle's law, for a given mass of ideal gas, pressure of gas is inversely proportional to the volume of gas, Provided the Temprature remains constant.

P₁ = 1.19 atmP₂ = ?V₁ = 18.7 LV₂ = 29.4 LT = constant = 24.4° C = Isothermal process

[tex]\implies \sf P_1 V_1 = P_2 V_2 \\ [/tex]

[tex]\implies \sf 1.19 \times 18. 7= P_2 \times 29.4 \\[/tex]

[tex]\implies \sf 22.253= P_2 \times 29.4 \\[/tex]

[tex]\implies \sf P_2 = \dfrac{22.253}{29.4} \\[/tex]

[tex]\implies \underline{ \red{\boxed{ \bf P_2 \approx0.756 \: atm }}} \\[/tex]

c6h5-c=o-ch3 + br2/oh

Answers

Explanation:

here's the molecule you were looking for

Please help with all 3 parts!

Answers

Answer:

1:Part A.

[tex]\bold{42.2 g C_{12}H_{22}O_{11} \:in \:528 g H₂O}[/tex]

Mass Percent=[tex]\bold{\frac{Mass\: of \:Solute}{Mass\: of \:Solution}×100\%}[/tex]

=[tex]\frac{42.2}{528}*100\%=\bold{\underline{7.99\: or \:8\%}}[/tex]

Part B.

[tex]\bold{198\:m g\: C_{6}H_{12}O_{6} \:in\:4.71 g\: H₂O}[/tex]

mass of solute: 198mg

mass of solvent :4.71g=4710g

Mass Percent=[tex]\bold{\frac{Mass\: of \:Solute}{Mass\: of \:Solution}×100\%}[/tex]

=[tex]\frac{198}{4710}*100\%=\bold{\underline{4.20\%}} [/tex]

Part C.

[tex]\bold{8.85 g NaCl \:in \:190 g\: H₂O}[/tex]

Mass Percent=[tex]\bold{\frac{Mass\: of \:Solute}{Mass\: of \:Solution}×100\%}[/tex]

=[tex]\frac{8.85}{190}*100\%=\bold{\underline{4.66\%}}[/tex]

Answer:

It will help you !!!!!!!!!!

how do elasticity ang flexibility differ?

Answers

Answer:

the object will regain its original form as soon as the deforming force is removed. ... Flexibility means the object is just easily deformed, and will stay that way.

Explanation:

HELP! How is the mass number of an atom calculated?
A - total number of electrons

B - total number of protons

C - protons plus neutrons

D - electrons plus neutrons

Answers

The answer is C. Mass number = protons + neutrons

Nicotine is a toxic substance present in tobacco leaves. There are two lone pairs in the structure of nicotine. In general, localized lone pairs are much more reactive than delocalized lone pairs. With this information in mind, do you expect both lone pairs in nicotine to be reactive?
A. Both lone pairs are delocalized and, therefore, both are expected to have the same reactivity.
B.Lone pair in pyrrolidine ring is localized and, therefore, is expected to be more reactive.
C. Both lone pairs are localized and, therefore, both are expected to be reactive.
D. Lone pair in pyridine ring is localized and, therefore, is expected to be more reactive.

Answers

Answer:

B.Lone pair in pyrrolidine ring is localized and, therefore, is expected to be more reactive.

Explanation:

There are two nitrogen atoms bearing lone pairs of electrons in the structure of nicotine as shown in the image attached.

One nitrogen atom is found in the pyrrolidine ring. The lone pair on this nitrogen atom is localized hence it is more reactive than the lone pair of electrons found on the nitrogen atom in the pyridine ring which is delocalized a shown in the image attached to this answer.

Balance the following equations Ag (s) + H₂ S(g) + 0₂ (g) → Ag₂ S(₅) + H₂0

Answers

Answer:

2Ag(s) + 2H²S(g) + O2(g) ➡️ Ag2S(s) + 2H2O(g)

Explanation:

Sorry for my typo. but you understand

Hydrogen is manufactured on an industrial scale by this sequence of reactions:

CH4(g) + H2O(g) ⇆ CO(g) + 3H2(g)
CO(g)+ H2O(g) ⇆ CO(g) + H2(g)

The net reaction is:
CH4(g) + H2O(g) ⇆ CO(g) + 4H2(g)

Write an equation that gives the overall equilibrium constant K in terms of the equilibrium constants K1 and K2.

Answers

Answer:

[tex]K=K_1*K_2\\\\K=\frac{[H_2]^3[CO_2][H_2]}{[CH_4][H_2O][H_2O]}[/tex]

Explanation:

Hello there!

In this case, for the given chemical reaction, it turns out firstly necessary to write the equilibrium expression for both reactions 1 and 2:

[tex]K_1=\frac{[CO][H_2]^3}{[CH_4][H_2O]} \\\\K_2=\frac{[CO_2][H_2]}{[CO][H_2O]}[/tex]

Now, when we combine them to get the overall expression, we infer these two are multiplied to get:

[tex]K=K_1*K_2\\\\K=\frac{[CO][H_2]^3}{[CH_4][H_2O]} *\frac{[CO_2][H_2]}{[CO][H_2O]}\\\\K=\frac{[H_2]^3[CO_2][H_2]}{[CH_4][H_2O][H_2O]}[/tex]

Regards!

90
1
39
is the
In the following decay equation,
90
Sy →
38
et
90
39
-1
A. alpha particle
B. parent element
C. daughter element
D. beta particle

Answers

Answer:

D. beta particle

Explanation:

Number of protons increases from 38 to 39 indicating beta decay (only one proton up from parent isotope to daughter isotope) Also atomic mass (on top of an isotope), 90 stays the same as beta particle is very small.

Which of the following statements is/are correct? 1. There are 5 orbitals in
the d subshell. 2. The d orbitals can accommodate 14 electrons. 3. The first
shell contains s and p orbitals. 4. The s orbital can accommodate 2 electrons.

A. 1 and 4
B. 2 and 3
C. 3 and 4
D. 2 and 4

Answers

?? Como dices entonces hablas english

calculate the pH of 0.01moldm-3 of trioxonitrate (v) acid​

Answers

Answer:

pH = 2

Explanation:

Trioxonitrate (v) acid​ is also known as nitric acid (HNO₃) and is one of the strong acid set which when dissolved in water, ionizes 100%. That is,

0.01M HNO₃ => 0.01M H⁺ + 0.01M NO₃⁻ => pH = -log[H⁺] = -log(0.01) = -(-2) = 2

An outdoor gear company develops a new type of fabric that works with electricity to warm the body without interfering with motion like heavy jackets do. Research biologists, studying life in extremely cold conditions on the polar ice caps, begin wearing the new fabric because it helps them work more comfortably, and they find it increases their productivity.

What best describes how the processes of scientific investigation and technological design are involved in this situation?

The clothing company conducted a scientific investigation to communicate results to researchers, who then used the knowledge in a technological design.
The clothing company conducted a scientific investigation to produce a product that researchers could then test while designing new technology.
The clothing company used technological design to create a product that helped aid researchers conducting a scientific investigation.
The clothing company designed a new technology that provided information researchers needed in order to continue with their scientific investigation.

Answers

The answer is C. The clothing company used technological design to create a product that helped aid researchers conducting a scientific investigation.

Answer:

C: The clothing company used technological design to create a product that helped aid researchers conducting a scientific investigation.

Explanation:

I just did the assignment on EDGE2020 and it's 200% correct!  

Also, heart and rate if you found this answer helpful!! :) (P.S It makes me feel good to know I helped someone today!!)  :)  

Calculate the solubility of copper(II) hydroxide, Cu(OH)2, in g/L​

Answers

Answer:

Ksp = [ Cu+² ] [ OH-] ²

molar mass Cu(oH )2 ==> M= 63.546 (1) + 16 (2) + 1 (2) = 97.546 g/mol

Ksp = [ Cu+² ] [ OH-] ²

Ksp [ cu (OH)2 ] = 2.2 × 10-²⁰

|__________|___Cu+² __|_2OH-____|

|Initial concentration(M)|___0__|_0______|

|Change in concentration(M)|_+S |__+2S__|

|Equilibrium concentration(M)|_S _|2S___|

Ksp = [ Cu+² ] [ OH-] ²

2.2 ×10-²⁰ = (S)(2S)²= 4S³

[tex]s = \sqrt[3]{ \frac{2.2 \times {10}^{ - 20} }{4} } = 1.8 \times {10}^{ - 7} [/tex]

S = 1.8 × 10-⁷ M

The molar solubility of Cu(OH)2 is 1.8 × 10-⁷ M

Solubility of Cu (OH)2 =

[tex]Cu (OH)2 = \frac{1.8 \times {10}^{ - 7} mol \:Cu (OH)2 }{1L} \times \frac{97.546 \: g \: Cu (OH)2}{1 \: mol \: Cu (OH)2} \\ = 1.75428 \times 10 ^{ - 5} [/tex]

Solubility of Cu (OH)2 = 1.75428 × 10 - g/ L

I hope I helped you^_^

What is the molarity of a solution that contains 17g of NH₃ in 0.50L of solution?

Please explain as well!

Answers

Explanation:

Because molarity is mol/L, we'll have to convert 17g to mol.

After obtaining the mol, we'll divide that by the volume to obtain Molarity.

Molar mass of Ammonia:-

[tex]\\ \sf\longmapsto NH_3[/tex]

[tex]\\ \sf\longmapsto 14u+3(1u)[/tex]

[tex]\\ \sf\longmapsto 14u+3u[/tex]

[tex]\\ \sf\longmapsto 17u[/tex]

[tex]\\ \sf\longmapsto 17g/mol[/tex]

Moles of Ammonia:-

[tex]\boxed{\sf No\:of\:moles =\dfrac{Given\:mass}{Molar\:mass}}[/tex]

[tex]\\ \sf\longmapsto No\:of\:moles=\dfrac{17}{17}[/tex]

[tex]\\ \sf\longmapsto No\;of\:moles=1mol[/tex]

Volume of solution=0.50L

We know

[tex]\boxed{\sf Molarity=\dfrac{Moles\:of\:solute}{Volume\:of\: Solution\:in\:L}}[/tex]

[tex]\\ \sf\longmapsto Molarity=\dfrac{1}{0.50}[/tex]

[tex]\\ \sf\longmapsto Molarity=2M[/tex]

How does a smoke detector utilize radiation?

A. Beta radiation creates a stead stream of electrons. When the stream is broken by smoke particles, it sets off the alarm.
B. Alpha radiation ionizes the air. When smoke interacts with the ionized particles it causes the alarm to sound.
C. Gamma radiation creates a stead stream of electrons. When the stream is broken by smoke particles, it sets off the alarm.
D. Beta radiation ionizes the air. When smoke interacts with the ionized particles it causes the alarm to sound.

Answers

D. Beta radiation ionizes the air. When smoke
interacts with the ionized particles it causes the
alarm to sound.

A piece of metal has a volume of 30.0cm3 and a mass of 252g. What is its density? what metal do you think this is?

Answers

Answer:

Explanation:

get density = D = m / V = 0.252 / 0.00003 = 8400 metal will be Cu => bronze

The density of a gas cannot be measured.
True
False

Answers

Answer:

False

Explanation:

Answer:

False

Explanation:

oxidation number of Ni in Ni(CO)4 is​

Answers

Answer:

0

Explanation:

answer from gauth math

12.39 HBr can be added to alkenes in either the absence or presence of peroxides (producing either the Markovnikov or the anti-Markovnikov addition product). What intermediates leading to the formation of the major product are observed when 1-butene is treated with 1) HBr or 2) HBr/peroxides

Answers

Answer:

See explanation and image attached

Explanation:

The reaction of HBr with 1-butene is an addition reaction. The HBr adds across the double bond to yield a saturated halogenoalkane.

In the absence of peroxides, the reaction proceeds in accordance with Markovnikov rule which states that;''the negative part of the addendum, is attached to the carbon atom with the least number of hydrogen atoms attached.'' This occurs in the first reaction shown in the image.

In the presence of peroxides, the reaction proceeds in an anti-Markovnikov manner to yield the product shown in the second reaction.

C2H5MgBr + PCl3 ra chất gì

Answers

Answer:

C2H5P

is the right answer

what is the mass of cerrusite would contain 35g of lead?​

Answers

Answer:

i believe its 42

Explanation:

For the following reaction, 5.29 grams of water are mixed with excess diphosphorus pentoxide. The reaction yields 13.3 grams of phosphoric acid . diphosphorus pentoxide(s) + water(l) phosphoric acid(aq). What is the theoretical yield of phosphoric acid?

Answers

Answer:

19.2 g

Explanation:

Step 1: Write the balanced equation

P₂O₅(s) + 3 H₂O(l) ⇒ 2 H₃PO₄

Step 2: Calculate the moles corresponding to 5.29 g of H₂O

The molar mass of H₂O is 18.02 g/mol.

5.29 g × 1 mol/18.02 g = 0.294 mol

Step 3: Calculate the theoretical yield of phosphoric acid, in moles

The molar ratio of H₂O to H₃PO₄ is 3:2. The theoretical yield of H₃PO₄ is 2/3 × 0.294 mol = 0.196 mol

Step 4: Calculate the mass corresponding to 0.196 moles of H₃PO₄

The molar mass of H₃PO₄ is 97.99 g/mol.

0.196 mol × 97.99 g/mol = 19.2 g

number is equal to 6022 x 10^23

Answers

Answer:

The Avogadro's number

Explanation:

the number is 6.02214x10 to the 23 power

Gimme the sandmeyer's reaction!!!​

Answers

Explanation:

HERE IS YOUR ANSWER.....

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PLEASE help me!!! Amina has two bags.In the first bag there are 3 red balls and 7 green balls.In the second bag there are 5 red balls and 4green balls.Amina takes at random a ball from the first bag.She then takes at random a ball from the second bag.(a) Complete the probability tree diagram. Name the element which used to produce the fungicide? (Use Pascal's triangle to expand each binomial. (x 5y)^5 She relies on Tom far too much. She doesnt take into account the possibility that he...her, in spite of his willingness to do so. please help have a lot of lessons Question 2 / 12Which two statements, when read together, prove that Suneeta is a vet at the zoo? Select two answers.None of Christopher's teammates aren't vetsJonathan is one of three vets at the zooSuneeta and Christopher are teammates at the zooO Suneeta is Jonathan's supervisorJonathan does not work on Christopher's team Read the following sentence and identify its type.Although he received the highest number of votes, he won only about 40%of the popular vote. Megan fails to see any connection between how hard she works and the size of her annual pay raises. Consequently, she no longer puts much effort into her job, even though she really wants a big raise. This best illustrates the importance of ________ in the operant conditioning of work habits. Group of answer choices 155 35 x x = ? 4) In a clinical test with 2353 subjects, 1136 showed improvement from the treatment. The length of a rectangle is 9 inches more than half the width. Find the length if the perimeter is 60 inches. Solve using Matlab the problems: One using the permutation of n objects formulaOne using the permutation of r objects out of n objectsYou can pick these problems from the textbook or you can make up your own questions.Help me pleaseeeee Find the length of the third side . How does the chemistry of the ocean change in response to high levels of CO2 in the atmosphere? if n(u) = 800. n(a) = 400. n(b) = 300 n(b) = 200 what is n(anb) and n(a) In 140 characters or less, choose three sentences from the Gettysburg address and write them in your own words. Please identify the sentences you are rewriting. You are Lincoln and you want to tweet the three most important sentences in one tweet. Gettysburg Address"Four score and seven years ago our fathers brought forth on this continent, a new nation, conceived in Liberty, and dedicated to the proposition that all men are created equal. Now we are engaged in a great civil war, testing whether that nation, or any nation so conceived and so dedicated, can long endure. We are met on a great battle-field of that war. We have come to dedicate a portion of that field, as a final resting place for those who here gave their lives that that nation might live. It is altogether fitting and proper that we should do this. But, in a larger sense, we can not dedicate -- we can not consecrate -- we can not hallow -- this ground. The brave men, living and dead, who struggled here, have consecrated it, far above our poor power to add or detract.The world will little note, nor long remember what we say here, but it can never forget what they did here. It is for us the living, rather, to be dedicated here to the unfinished work which they who fought here have thus far so nobly advanced. It is rather for us to be here dedicated to the great task remaining before us -- that from these honored dead we take increased devotion to that cause for which they gave the last full measure of devotion -- that we here highly resolve that these dead shall not have died in vain -- that this nation, under God, shall have a new birth of freedom -- and that government of the people, by the people, for the people, shall not perish from the earth." - Abraham Lincoln graph a line with the slope of -5 and the y intercept of 4PLEZZ HELP!!!!!!!!!!!!!!!! it give f(x) = x-3x +2x -4x +5x -10 and f(4)(x)? An airline records data on several variables for each of its flights: model of plane, amount of fuel used, time in flight, number of passengers, and whether the flight arrived on time. The number and type of variables recorded are a. 1 categorical, 4 quantitative (1 discrete, 3 continuous) b. 1 categorical, 4 quantitative (2 discrete, 2 continuous) c. 2 categorical, 3 quantitative (1 discrete, 2 continuous) d. 2 categorical, 3 quantitative (2 discrete, 1 continuous) e. 3 categorical, 2 quantitative (1 discrete, 1 continuous) In order to test an intentionally weak adhesive, the bottom of the small 0.15-lb block is coated with adhesive and then the block is pressed onto the turntable with a known force. The turntable starts from rest at t = 0 and uniformly accelerates with a = 2 rad/s^2. If the adhesive fails at exactly t = 3 s, then determine: a. the magnitude of the ultimate shear force that the adhesive supports b. the angular displacement of the turntable at the time of failure