Answer:
The correct answer is option C. The unknown solution definitely has Hg22+ present.
Explanation:
In the analysis of group 1 metal cation, the unknown solution is treated with sufficient quantity of 6 M HCl solution and if group 1 metal cations are present then white precipitate of Agcl, PbCl2 or Hg2Cl2 is formed. The precipitate of PbCl2 is soluble in hot water but the other two remains insoluble after treating with hot water. Precipitate of AgCl disappears upon treatment of NH3 solution but Hg2Cl2 becomes black in the reaction with NH3. The black Colour appears due to the formation of metallic Hg.
Balanced chemical equation of the reation is -
Hg2Cl2 + 2NH3 ---------> HgNH2Cl (white ppt.) + Hg (black ppt.) + NH4Cl
Therefore, from the given information the conclusion which can be drawn is that the unknown solution definitely has Hg22+ present.
Answer:
C- the unknown solution definitely has Hg22+ present.
Explanation:,
Standard reduction potentials for zinc(II) and copper(II) The standard reduction potential for a substance indicates how readily that substance gains electrons relative to other substances at standard conditions. The more positive the reduction potential, the more easily the substance gains electrons. Consider the following: Zn2+(aq)+2e−→Zn(s),Cu2+(aq)+2e−→Cu(s), E∘red=−0.763 V E∘red=+0.337 V
The question is incomplete, the complete question is:
Standard reduction potentials for zinc(II) and copper(II)
The standard reduction potential for a substance indicates how readily that substance gains electrons relative to other substances at standard conditions. The more positive the reduction potential, the more easily the substance gains electrons. Consider the following:
Zn2+(aq)+2e−→Zn(s),Cu2+(aq)+2e−→Cu(s), E∘red=−0.763 V E∘red=+0.337 V
Part B
What is the standard potential, E∘cell, for this galvanic cell? Use the given standard reduction potentials in your calculation as appropriate.
Express your answer to three decimal places and include the appropriate units.
Answer:
1.100 V
Explanation:
E∘cell= E∘cathode - E∘anode
E∘cathode= +0.337 V
E∘anode= −0.763 V
E∘cell= 0.337-(-0.763)
E∘cell= 1.1V
The following reaction was followed by the method of initial rates: 5 Br-(aq) + BrO3-(aq) + H+(aq) → 3 Br2(aq) + 3 H2O(l) with the following results. Exp [Br− ]0 [BrO3− ] H+ (Δ[BrO3− ]/Δt)0 M·s−1 I 0.10 0.10 0.10 6.8 10-4 II 0.15 0.10 0.10 1.0 10-3 III 0.10 0.20 0.10 1.4 10-3 IV 0.10 0.10 0.25 4.3 10-3 Please see Determine Rate Laws for assistance. What is the rate law for the reaction? (Example input 'rate = k . [A]^2 . [B]'.)
Answer:
rate = k [Br⁻][H⁺]²[BrO₃⁻]
Explanation:
Here we are going to determine the rate law for the reaction
5 Br-(aq) + BrO3-(aq) + H+(aq) → 3 Br2(aq) + 3 H2O(l)
by performing experiments in which we vary concentration of the reactants and determining the effect this has on the initial rate.
Exp [ Br− ] [BrO3− ] [ H+] (Δ[BrO3− ]/Δt)0 M·s−1
I 0.10 0.10 0.10 6.8 x 10-4
II 0.15 0.10 1.0 10-3
III 0.10 0.20 0.10 1.4 x 10-3
IV 0.10 0.10 0.25 4.3 10-3
The way to do the comparison is by taking experiments in which we keep constant the concentration of two of the reactants and vary the third and study the effect this change has on the initial rate of the reaction.
Comparing experiments I and III we see that the initial reaction doubled when we doubled the [BrO3− ] while keeping the other two the same. Thus the reaction rate is of order 1 respect to [BrO3− ].
In experiments I and IV we increased the concentration of H⁺ by 2.5 times, and the rate of the reaction increased by a factor of 6.3 which is 2.5 squared . If you do not see it, lets try using logarithms
(0.25/ 0.10)^ x = 4.3 x 10⁻³ / 6.8 x 10⁻⁴
2.5 ^ x = 6.3235
x log 2.5 = log 6.3235
0.40 x = 0.80 ∴ x = 2
Therefore the rate is second order respect to [H⁺].
Comparing experiments I and II we see that increasing the concentration of Br⁻ by a factor of 1.5, the initial rate also went up by a factor of 1.5 ( 1.0 x 10⁻³ / 6.8 x 10⁻⁴ =1.5. Thus the rate is first order respect to [ Br⁻ ].
Then our rate law is
rate = k [Br⁻][H⁺]²[BrO₃⁻]
The rate law for the reaction 5 Br-(aq) + BrO3-(aq) + H+(aq) → 3 Br2(aq) + 3 H2O(l) is determined to be rate = k[Br-]^1[BrO3-]^1[H+]^0 by analyzing how the rate changes with varying initial concentrations of the reactants.
Explanation:To determine the rate law for the reaction: 5 Br-(aq) + BrO3-(aq) + H+(aq) → 3 Br2(aq) + 3 H2O(l), we need to examine how the rate changes with varying initial concentrations of the reactants. The change in rates as concentrations are altered provides the order of reaction with respect to each reactant. Our data from experiments I, II, and III indicate that when the Br- concentration increases by a factor of 1.5 (from 0.10 to 0.15), the rate also increases by a similar factor (from 6.8 x 10-4 to 1.0 x 10-3), suggesting a first-order dependence: [Br-]^1. However, when we double the initial concentration of BrO3 (experiment III vs I), the rate also doubles indicating first-order dependence on BrO3 as well: [BrO3]^1. The experiment IV suggests a zero-order dependence on [H+]. Hence, the rate law for this reaction is rate = k[Br-]^1[BrO3-]^1[H+]^0, where k is the rate constant.
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The quantity of heat required to change the temperature of 1 g of a substance by 1°C is defined as ____.
a joule
a calorie
density
specific heat
Answer:
specific heat
Explanation:
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Please help! The Michael reaction is a conjugate addition reaction between a stable nucleophilic enolate ion (the donor) and an α,β-unsaturated carbonyl compound (the acceptor). 1.) Draw the structure of the product of the Michael reaction between ethyl propenoate and 3-oxobutanenitrile.2.)The Michael reaction is a conjugate addition reaction between a stable nucleophilic enolate ion (the donor) and an α,β-unsaturated carbonyl compound (the acceptor). Draw the structure of the product of the Michael reaction between propenamide and 2,4-pentanedione.
Answer:
See explaination andd attachment
Explanation:
Treatment of aldehydes and ketones with a suitable base can lead to the formation of a nucleophilic species called an enolate that reacts with electrophiles. These C nucleophiles are useful for making new carbon-carbon bonds.
Please kindly see attachment for the drawings.
A salt bridge: Question 3 options: provide a pathway through which the electrons travel from the cathode to the anode. provide a pathway through which the electrons travel from the anode to the cathode. provide a source of counterions to prevent the build-up of charge at both the cathode to the anode. provide a physical connection between the two cells, allowing the solutions in both cells to slowly mix.
Answer:
The correct option is: provide a source of counterions to prevent the build-up of charge at both the cathode to the anode.
Explanation:
A salt bridge is a U-shaped glass tube that is used in a voltaic cell or galvanic cell to connect the oxidation and reduction half-cells and complete the electric circuit.
It allows the ions to pass through it, thus preventing the accumulation of charge on the anode and cathode as the chemical reaction proceeds.
Therefore, the correct option is: provide a source of counterions to prevent the build-up of charge at both the cathode to the anode.
1. Compare and contrast the rate of solution formation between the three physical forms of salt that were placed in the vial and not agitated with the three forms of salt that were placed in the vial and were agitated.
Answer:
Explanation:
The salt that was in pellet form took the longest time before it could be dissolved during all the trials. The salt with fine texture dissolves first during the trials, and the salt with coarse texture took the middle position during all the trials.
Salt with agitation dissolves faster than salts without any agitation.
Transport of aspirin is expected to be faster in the ____. The speed of nonmediated absorption depends strongly on the polarity and charge of molecules. When p H is low (as it is in the _______), the aspirin molecule will be _______ and thus _______, due to _____ of H+ in the solution. The higher pH is, the _______ charged and polar will become the molecule, leading to the ____--- in the speed of absorption. One more evidence to this conclusion is that the pH in the _______ is much lower than pKa of aspirin comparing to the pH of the _______.
The missing words in the blanks are-
Stomach Stomach highly protonated uncharged high concentration more decrease stomach intestine.The transport of aspirin is more in the bloodstream from the stomach as absorption speed depends on the polarity and charge of molecules of the aspirin.
The pH of the stomach is low then molecules of aspirin become highly protonated due to the high concentration of H+ ion they are uncharged.So it is clear that an increase in pH charge and polarity of the molecules also increases which causes less absorption speed of molecules.the pKa of aspirin in the intestine is much more than the pH in the stomach.Thus,
The missing words in the blanks are-
Stomach Stomach highly protonated uncharged high concentration more decrease stomach intestine.Learn more:
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What is the Kelvin temperature of the air in a tire if the pressure inside the tire is 188 kPa at 32°C. While driving under perilous road conditions on a hot road; the pressure in the tire has increased to 225 kPa.
Answer:
414KExplanation:
The question is not completely clear because some missing parts or grammar (syntax) errors.
Interpreting it, the question is what is the Kelvin temperatue of the air in a tire, when the pressure in the tire has increased to 225 kPa, if the initial conditions of the air inside the tire were 188kPa of pressure and a temperature of 32ºC.
To solve this, you can assume constant volume and use the law of Gay-Lussac for ideal gases:
[tex]\dfrac{P_1}{T_{1}}=\dfrac{P_2}{T_2}[/tex]
That equation works with absolute temperatures, i.e. Kelvin.
32ºC = 32 + 273.15 K = 305.15KThen solve for T₂, substitute and compute:
[tex]T_2=P_2\times \dfrac{T_1}{P_{1}}=225kPa\times \dfrac{305.15K}{188kPa}[/tex]
[tex]T_2=413.90K\approx 414K\longleftarrow answer[/tex]
What is the mass of 0.75 moles of (NH4)3PO4?
The mass of (NH4)3PO4 is 111.75grams.
HOW TO CALCULATE THE MASS:
The mass of a substance can be calculated by multiplying the number of moles by its molecular mass. That is;mass (g) = moles (mol) × molar mass (g/mol)
Molar mass of (NH4)3PO4 is calculated as follows:{14 + 1(4)}3 + 31 + 16(4)
= (14+4)3 + 31 + 64
= 54 + 31 + 64
= 149g/mol
mass in grams = 149 × 0.75
mass in grams = 111.75g
Therefore, the mass of (NH4)3PO4 is 111.75grams.
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Balance the redox reaction by inserting the appropriate coefficients.
H2O + Br- + Al3- = Al + BrO3- + H+
The balanced equation is given as,
2Al³⁺ + 3H₂O + Br⁻ → 2 Al + BrO³⁻ + 6H⁺
Explanation:
H₂O + Br⁻ + Al³⁺ → Al + BrO₃⁻ + H⁺
Here the half reactions are:
Al³⁺→ Al [reduction]
Br⁻ → BrO₃⁻ [oxidation]
Now we have to balance the half reactions as,
Al³⁺ + 3e⁻ → Al
To balance H atoms we have to add water and electrons.
3H₂O + Br⁻→ BrO³⁻ + 6H⁺ + 6e⁻
Now we have to balance the electrons as,
2Al³⁺ + 6e⁻ → 2 Al
3H₂O + Br⁻→ BrO³⁻ + 6H⁺ + 6e⁻
Now we have to add both the equations as,
2Al³⁺ + 6e⁻ + 3H₂O + Br⁻ → 2 Al + BrO³⁻ + 6H⁺ + 6e⁻
6 electrons on both sides of the equation gets cancelled and so the balanced reaction can be written as,
2Al³⁺ + 3H₂O + Br⁻ → 2 Al + BrO³⁻ + 6H⁺
The student realizes that the precipitate was not completely dried and claims that as a result, the calculated Na2CO3 molarity is too low. Do you agree with the student’s claim? Justify your answer
Answer:I disagree, the molarity is meant to be higher if all other factors remain constant.
Explanation:
Molarity=amount of substance/volume of the liquid
So,the lesser,the volume, the higher the molarity and vice versa.
The molarity calculation of Na2CO3 could indeed be lower if the precipitate was not adequately dried. Excess moisture adds to the mass, misrepresenting the actual quantity of Na2CO3, which may lead to a lower calculated molarity.
Explanation:In the field of chemistry, the student's claim about the molarity of Na2CO3 (sodium carbonate) being inaccurately low due to incomplete drying of the precipitate can be valid. As the drying process helps in removing water molecules from the precipitate, any remaining moisture can add extra mass, causing the quantity of pure Na2CO3 to be undervalued. While calculating the molarity, this would imply more volume per mole, hence a lower molarity. This is a common issue in stoichiometry where proper handling and processing of chemical substances significantly affect the outcome of calculations.
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In the laboratory you are given the task of separating Ag+ and Cu2+ ions in aqueous solution.
For each reagent listed below indicate if it can be used to separate the ions. Type "Y" for yes or "N" for no. If the reagent CAN be used to separate the ions, give the formula of the precipitate. If it cannot, type "No"
Y or N Reagent Formula of Precipitate if YES
1. NaI
2. K2S
3. K2CO3
Answer:
1. NaI Y AgI
2. K2S Y CuS
3. K2CO3 N
Explanation:
1. When we add NaI to the mixture, the reaction that takes place is:
NaI(aq) + Ag⁺(aq) → AgI(s) + Na⁺(aq)Such a reaction does not happen with Cu⁺².
2. When we add K₂S to the mixture, the reaction that takes place is:
K₂S(aq) + Cu⁺²(aq) → CuS(s) + 2K⁺(aq)Such a reaction does not happen with Ag⁺.
3. When we add K₂CO₃ to the mixture, the reactions that take place are:
K₂CO₃(aq) + 2Ag⁺(aq) → Ag₂CO₃(s) + 2K⁺(aq)K₂CO₃(aq) + Cu⁺²(aq) → CuCO₃(s) + 2K⁺(aq)This means both Cu⁺² and Ag⁺ would precipitate, thus they would not be separated.
Bromobenzene is converted to a compound with the molecular formula C7H7Br in the reaction scheme below. Draw the structures of the product and the two intermediates, and identify the reagents in each of the three steps.
Complete Question:
The first file attached contains the complete question
Answer:
The reagents play a vital role in a reaction to undergo a transformation. Each reagent plays a different role in the chemical reaction.
Grignard reagent: Grignard reagent R - Mg - X . R represents an alkyl group or aryl group. X represents halides (I,Br,Cl) . The main purpose of a Grignard reagent is the formation of new C−C bond. Grignard reagent undergoes reaction with carbonyl groups (like ketone ( {\rm{ - C = O}}−C=O ), Aldehyde ( - C( = O)H}}−C(=O)H ), Ester ( - C( = O)OR}}−C(=O)OR )) to form an addition product.
Nucleophilic addition: the addition of nucleophile (electron rich) with electrophiles (electron deficient). In this reaction, the double bond is converted to a single bond.
Nucleophilic substitution: In this, the Nucleophile (electron rich) forms a bond with an electrophile (electron deficient) and replaces the leaving group.
The attached file contained detailed solution
You have been asked to prove that the Oil Spill Eater speeds up the reaction as you found above. Describe the basic set up of a laboratory experiment to measure the effect of enzyme on an oil spill in the ocean. Select all necessary test reactions. Group of answer choices Run a test reaction of crude oil with ocean water over time without Oil Spill Eater present. Run a test reaction of crude oil at a cool temperature with Oil Spill Eater present Run a test reaction of crude oil with ocean water over time with Oil Spill Eater present. Run a test reaction of crude oil at a warm temperature with Oil Spill Eater present Run a test reaction of crude oil at a warm temperature without Oil Spill Eater present Run a test reaction of crude oil at a cool temperature without Oil Spill Eater present
Answer:
The correct answer is option 3. Run a test reaction of crude oil with ocean water over time with Oil Spill Eater present
Explanation:
In any laboratory experiment, all the apparatus needed to carry out a particular experiment must be provided. In this case, our apparatus will be crude oil with ocean water and oil spill eater which is the enzyme used.
We can then run a test reaction of crude oil with ocean water over time with Oil Spill Eater present.
Fatty acid oxidation occurs in the mitochondrial matrix. However, long-chain fatty acyl-CoA molecules cannot cross the inner membrane to enter the matrix. The carnitine shuttle system transfers the acyl group from CoA to carnitine, which can enter the mitochondrial matrix. Label the enzymes and compounds of the carnitine shuttle system. These abbreviations are used: intermembrane space, IMS; carnitine acyltransferase I, CAT1; mitochondrial carnitine acyltransferase II, CAT2; and carnitine/acylcarnitine translocase (carnitine carrier protein), CAT.
Answer:
Explanation:
see answer below in the attached file.
The carnitine shuttle system is an important system that helps in the fatty acid oxidation.
The functions of the enzymes and compounds of the carnitine shuttle system include the following:
Intermembrane space (IMS): The activities of the enzymes of the carnitine system takes place in this space within the cells.Carnitine acyltransferase I, (CAT1): This is also called Carnitine palmitoyltransferase 1. It converts long-chain acyl-CoA species to their corresponding long-chain acyl-carnitines for transport into the mitochondria.Mitochondrial Carnitine acyltransferase II, CAT2: This is an enzyme found inside the mitochondria that oxidizes long-chain fatty acids in the mitochondria.carnitine/acylcarnitine translocase (carnitine carrier protein), CAT: This is a membrane transporter that exchanges cytoplasmic acylcarnitine for mitochondrial carnitine.Learn more here:
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How many liters would you need to make a 0.7 M solution if you have 3.34 mol of Potassium
Chloride?
The volume of Potassium chloride solution is 4.8 L.
Explanation:
Molarity is found by dividing the number of moles of the given substance by its volume in litres, and so the unit of molarity is mol/L.
Here number of moles is given as 3.34 mol
Molarity = 0.7 M
Volume = ? L
Molarity = [tex]$\frac{moles}{Volume (L) }[/tex]
To find the volume we have to rearrange the equation as,
Volume (L) = [tex]$\frac{moles}{molarity}[/tex]
Now, we have to plug in the values as,
Volume (L) = [tex]$\frac{3.34 mol}{0.7 mol/L}[/tex]
= 4.77 ≈ 4.8 L
So the volume of Potassium chloride solution is 4.8 L.
To prepare a buffer you weigh out 7.20 grams of NaHCO3 and place it into a 400.00 mL volumetric flask. To this flask you add 56.0 mL of 5.60 M H2CO3 and then fill it about halfway with distilled water, swirling to dissolve the contents. Finally, the flask is filled the rest of the way to the mark with distilled water.What is the pH of the buffer that you have created?Acid KaH2CO3 4.3 X 10⁻⁷ HCN 4.9 X 10⁻¹⁰HNO2 4.6 X 10⁻⁴C6H5COOH 6.5 X 10⁻⁵
Answer:
pH = 5.80
Explanation:
The buffer solution is:
H₂CO₃(aq) + H₂O(l) ⇄ HCO₃⁻Na⁺(aq) + H₃O⁺(aq)
To find the pH of the buffer solution we will use the Henderson-Hasselbalch equation:
[tex]pH = pKa + log(\frac{[NaHCO_{3}]}{[H_{2}CO_{3}]})[/tex] (1)
First, we need to find the concentration of the buffer solution. For the NaHCO₃ we have:
[tex][NaHCO_{3}] = \frac{mol}{V} = \frac{m}{M*V}[/tex]
Where:
m: is the mass of the NaHCO₃ = 7.20 g
M: is the molar mass of the NaHCO₃ = 84.007 g/mol
V: is the volume of the solution = 400.0 mL
Hence, the concentration of NaHCO₃ is:
[tex][NaHCO_{3}] = \frac{7.20 g}{84.007 g/mol*400.0 \cdot 10^{-3} L} = 0.214 M[/tex]
Now, the concentration of H₂CO₃ is:
[tex] V_{i}C_{i} = V_{f}C_{f} [/tex]
Where:
Vi: is the initial volume of H₂CO₃ = 56.0 mL
Ci: is the initial concentration of H₂CO₃ = 5.60 M
Vf: is the final volume of H₂CO₃ = 400.0 mL
Cf: is the final concentration of H₂CO₃ (to find)
[tex] C_{f} = \frac{V_{i}C_{i}}{V_{f}} = \frac{56.0 mL*5.60 M}{400.0 mL} = 0.784 M [/tex]
Finally, we can use the equation (1) to find the pH of the buffer solution:
[tex] pH = -log(4.3 \cdot 10^{-7}) + log(\frac{0.214 M}{0.784 M}) = 5.80 [/tex]
I hope it helps you!
You have studied the gas-phase oxidation of HBr by O2: 4 HBr(g) + O2(g) → 2 H2O(g) + 2 Br2(g) You find the reaction to be first order with respect to HBr and first order with respect to O2. You propose the following mechanism: HBr(g) + O2(g) → HOOBr(g) HOOBr(g) + HBr(g) → 2 HOBr(g) HOBr(g) + HBr(g) → H2O(g) + Br2(g) a. Confirm that the elementary reactions add to give the overall reaction. (Hint: Use Hess Law) b. Based on the experimentally determined rate law, which step is rate determining? c. What are the intermediates in this mechanism? d. If you are unable to detect HOBr or HOOBr among the products, does this disprove your mechanism?
In the oxidation of HBr by O2, the elementary reactions add up to give the overall reaction and thus confirm Hess's Law. The rate determining step is the first one, and the intermediates in the reaction are HOOBr and HOBr. The inability to detect these among the final products does not disprove this mechanism.
Explanation:The overall reaction for the gas-phase oxidation of HBr by O2 is written as: 4 HBr(g) + O2(g) → 2 H2O(g) + 2 Br2(g)
First, we need to confirm if the elementary reactions add up to the overall reaction. Based on Hess's Law, we can see that if we add the elementary reactions: HBr(g) + O2(g) → HOOBr(g), HOOBr(g) + HBr(g) → 2 HOBr(g), and HOBr(g) + HBr(g) → H2O(g) + Br2(g), they give the same overall reaction, thus confirming Hess's Law.
Second, the experimentally determined rate law is first order with respect to both HBr and O2, which suggests the rate determining step is the first one: HBr(g) + O2(g) → HOOBr(g). This is because the rate-determining step usually determines the order of the reaction.
The intermediates in this reaction are the species that are produced in one step and consumed in another, in this case HOOBr(g) and HOBr(g).
Lastly, the inability to detect HOBr or HOOBr among the final products does not necessarily disprove the mechanism. This is because these are intermediates and are typically used up in subsequent reaction steps, leading them to not appear in the final product of the reaction.
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The given elementary steps add up to the overall reaction. The rate-determining step involves HBr and O₂ as indicated by the rate law. HOBr and HOOBr are intermediates, and their absence among products does not disprove the mechanism.
let's analyze and confirm each part.
a. Confirming the Elementary Reactions:
The given elementary steps are:
HBr(g) + O₂(g) → HOOBr(g)HOOBr(g) + HBr(g) → 2 HOBr(g)HOBr(g) + HBr(g) → H₂O(g) + Br₂(g)Adding these reactions together:
1st Step: HBr(g) + O₂(g) → HOOBr(g)2nd Step: HOOBr(g) + HBr(g) → 2 HOBr(g)3rd Step: HOBr(g) + HBr(g) → H₂O(g) + Br₂(g)Combining the species on both sides gives us:
4 HBr(g) + O₂(g) → 2 H₂O(g) + 2 Br₂(g)
This confirms that the elementary steps add up to the overall reaction.
b. Rate-Determining Step:
The given rate law is first order with respect to both HBr and O₂, indicating that the rate-determining step involves one molecule each of HBr and O₂. Hence, the first step, HBr(g) + O₂(g) → HOOBr(g), is the rate-determining step.
c. Intermediates:
Intermediates are species that appear in the reaction mechanism but not in the overall reaction. Here, HOOBr and HOBr are intermediates.
d. Detecting Intermediates:
Not detecting HOBr or HOOBr among the products does not disprove the mechanism. Intermediates typically have short lifespans and do not accumulate significantly; hence they might not be detected in significant amounts in the product mixture.
The Michael reaction is a conjugate addition process wherein a nucleophilic enolate anion (the donor) reacts with an α,β-unsaturated carbonyl compound (the acceptor). The best Michael reactions are those that take place when a particularly stable enolate anion is formed via treatment of the donor with a strong base. Alternatively, milder conditions can be used if an enamine is chosen as the donor, this variant is termed the Stork reaction. In the second step, the donor adds to the β-carbon of the acceptor in a conjugate addition, generating a new enolate. The enolate abstracts a proton from solvent or from a new donor molecule to give the conjugate addition product.
Draw curved arrows to show the movement of electrons in this step of the mechanism.
Answer:
See the attached file for the structure
Explanation:
See the attached file
Consider this reaction occurring at 298 K: N2O(g) + NO2(g) 2 3 NO(g) a. Show that the reaction is not spontaneous under standard conditions by calculating A Grx b. If a reaction mixture contains only N20 and NO2 at partial pressures of 1.0 atm each, the reaction will be spontaneous until some NO forms in the mixture. What maximum partial pressure of NO builds up before the reaction ceases to be spontaneous? c. Can the reaction be made more spontaneous by an increase or decrease in temperature? If so, what temperature is required to make the reaction spontaneous under standard conditions?
Answer:
A.) ΔG = 107.8 kJ/mol
ΔG rxn is positive implies that the reaction is non spontaneous.
B) P (NO) = 5.0 x 10^-7 atm
C) T > 923.4 K, therefore, the temperature should be 924K in order to make the reaction spontaneous.
Explanation:
N2O(g) + NO2(g) - 3NO(g)
A) ΔG = ΔG products - ΔG reactants
ΔGf (N2O) = 103.7 kJ/mol
ΔGf (NO2) = 51.3 kJ/mol
ΔGf (NO) = 87.6 kJ/mol
ΔG rxn = 3*87.60 - (103.7 + 51.3)
= 107.8 kJ/mol
ΔG rxn is positive implies that the reaction is non spontaneous.
(B). P (N2O) = P (NO2) = 1 atm
ΔG rxn = ΔG°rxn + RTln(K)
ΔG rxn = ΔG°rxn + RT×ln (P NO)^3 / [P(N2O) × P(NO2)]
When the reaction ceases to be spontaneous, then ΔG rxn = 0.
0 = 107.8 × 10^3 + 8.314 × 298 × ln (P NO)^3 / (1 * 1)
107.8 × 10^3 = - 8.314 × 298 × ln (P NO)^3
ln (P NO)^3 = - 43.51
3 × ln (P NO) = - 43.51
ln (P NO) = -14.50
P (NO) = e^(-14.50)
P (NO) = 5.0 x 10^-7 atm
(C). For a reaction to be spontaneous, ΔG rxn should be negative.
It is known that:
ΔG= ΔH - TΔS
ΔG= ΔH - TΔS < 0
ΔH< TΔS
T < ΔH / ΔD
For the reaction:
ΔH = 3×NO - (N2O + NO2)
= 3×(91.3) - (81.6 + 33.2)
= 159.1 kJ/mol
ΔS = 3×210.8 - (220.0 + 240.1)
= 172.3 J/mol.K
= 0.1723 kJ/mol.K
From the above expression.
T > 159.1 / 0.1723
T > 923.4 K
Therefore, the temperature should be 924K in order to make the reaction spontaneous.
When 102 g of water at a temperature of 22.6 °C is mixed with 66.9 g of water at an unknown temperature, the final temperature of the resulting mixture is 48.9 °C. What was the initial temperature of the second sample of water? (The specific heat capacity of liquid water is 4.184 J/g ⋅ K.) Initial temperature = °C
Answer:
[tex]T_{2,H_2O}=89^oC[/tex]
Explanation:
Hello,
In this case, we notice that the energy gained by the first sample of water is lost by the second sample of water as they are heated and cooled respectively, therefore, in terms of heats:
[tex]Q_{1,H_2O}=-Q_{2,H_2O}[/tex]
Which in terms of masses, heat capacities and temperatures is:
[tex]m_{1,H_2O}*Cp_{1,H_2O}*(T_{EQ}-T_{1,H_2O})=-m_{2,H_2O}*Cp_{2,H_2O}*(T_{EQ}-T_{2,H_2O})[/tex]
In such a way, as the heat capacity is the same and the initial temperature of the cold water is required, we solve for it via:
[tex]m_{1,H_2O}*(T_{EQ}-T_{1,H_2O})=-m_{2,H_2O}*(T_{EQ}-T_{2,H_2O})\\T_{EQ}-T_{2,H_2O}=\frac{m_{1,H_2O}*(T_{EQ}-T_{1,H_2O})}{-m_{2,H_2O}} \\\\T_{2,H_2O}=T_{EQ}+\frac{m_{1,H_2O}*(T_{EQ}-T_{1,H_2O})}{m_{2,H_2O}}[/tex]
With the given data we obtain:
[tex]T_{2,H_2O}=T_{EQ}+\frac{m_{1,H_2O}*(T_{EQ}-T_{1,H_2O})}{m_{2,H_2O}}\\\\T_{2,H_2O}=48.9^oC+\frac{102g*(48.9^oC-22.6^oC)}{66.9g} =48.9^oC+40.1^oC\\T_{2,H_2O}=89^oC[/tex]
Which means the second sample was hot.
Regards.
Answer:
The initial temperature of the second sample of water is 8.8 °C
Explanation:
Step 1 :Data given
Mass of water = 102 grams
Initial temperature of water = 22.6 °C =
Mass of other water = 66.9 grams
The final temperature is 48.9 °C
The specific heat capacity of liquid water is 4.184 J/g *K = 4.184 J/g°C
Step 2: Calculate the initial temperature of the second sample water
Heat gained = heat lost
Qgained = -Q lost
Q = m* C* ΔT
m(water1)*C(water)*ΔT(water1) = -m(water2) * C(water) *ΔT(water2)
⇒with m(water1) = the mass of the water at 22.6 °C = 102 grams
⇒with C(water) = the specific heat of water = 4.184 J/g°C
⇒with ΔT = the change of water of the first sample = 48.9 - 22.6 = 26.3 °C
⇒with m(water2) = the mass of the other unknown sample water = 66.9 grams
⇒with with C(water) = the specific heat of water = 4.184 J/g°C
⇒with ΔT = the change of water of the second sample = 48.9 - T1
102 * 4.184 * 26.3 °C = 66.9 * 4.184 * (48.9 - T1)
102 * 26.3 = 66.9 * (48.9 - T1)
2682.6 = 3271.4 - 66.9 T1
-588.8 = -66.9 T1
T1 = 8.8 °C
The initial temperature of the second sample of water is 8.8 °C
A σ bond arises from the straight-on overlap of two atomic orbitals. The electron density lies along the axis of the two bonded nuclei. Example: Sigma Bonding in methane, CH4 What atomic or hybrid orbital on the central I atom makes up the sigma bond between this I and an outer Br atom in iodine tribromide, IBr3 ?
In iodine tribromide, the I-Br sigma bond is formed through the straight-on overlap of sp3d hybrid atomic orbitals on iodine with p orbitals on bromine.
Explanation:In iodine tribromide (IBr3), the central iodine (I) atom is surrounded by three bromine (Br) atoms. The I-Br bond that forms is a sigma (σ) bond, which is the result of a straight-on overlap of atomic orbitals. Sigma bonding typically involves the hybridized orbitals. Specifically, in IBr3, the I atom undergoes hybridization and forms two lone pairs and three σ bonds with Br atoms using sp3d hybrid orbitals. So, the hybrid orbital on the iodine atom that makes up the σ bond with a bromine atom is the sp3d hybrid orbital.
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The sigma bond in IBr3 between the central I atom and an outer Br atom is formed by the overlap of a sp3d hybrid orbital from iodine with a p orbital from bromine to accommodate the T-shaped geometry of the molecule.
In iodine tribromide (IBr3), the sigma bond between the central iodine (I) atom and an outer bromine (Br) atom is typically formed by the overlap of a hybrid orbital from the iodine with a p orbital from the bromine. When we consider the valence shell electronic configuration of iodine (5s2 5p5), upon forming IBr3, three of the p orbitals would be used to form sigma bonds with the bromine atoms, and this would likely involve hybridization to accommodate the molecular geometry of IBr3. The exact nature of the hybrid orbitals would depend on the geometry of the molecule, which, due to the presence of only three bond pairs and two lone pairs, adopts a T-shaped geometry, pointing towards sp3d hybridization. However, the exact details of this hybridization can only be confirmed with molecular orbital calculations
A typical refrigerator is kept at 4˚C, and a soda can has a pressure of
1.18 atm. The inside of a car can reach up to 60˚C (140˚F) when it is left in
direct sunlight on a hot day. If you left the soda can in the car, what would
be the new pressure if it reached 60˚C?
Answer: The new pressure will be 1.42 atm
Explanation:
To calculate the final pressure of the system, we use the equation given by Gay-Lussac Law. This law states that pressure of the gas is directly proportional to the temperature of the gas at constant pressure.
Mathematically,
[tex]\frac{P_1}{T_1}=\frac{P_2}{T_2}[/tex]
where,
[tex]P_1\text{ and }T_1[/tex] are the initial pressure and temperature of the gas.
[tex]P_2\text{ and }T_2[/tex] are the final pressure and temperature of the gas.
We are given:
[tex]P_1=1.18atm\\T_1=4^0C=(4+273)K=277K\\P_2=?\\T_2=60^0C=(60+273)K=333K[/tex]
Putting values in above equation, we get:
[tex]\frac{1.18}{277}=\frac{P_2}{333}\\\\P_2=1.42[/tex]
Hence, the new pressure will be 1.42 atm
Which of the following is the net ionic equation for the reaction that occurs when a few drops of HCl are added to a buffer containing a weak base (B) and its conjugate acid (BH+)? B(aq) + OH−(aq) → BOH−(aq) BH+(aq) + OH−(aq) → H2O(l) + B(aq) H+(aq) + OH−(aq) → H2O(l) H+(aq) + B(aq) → BH+(aq) B(aq) + H2O(l) begin mathsize 12px style rightwards harpoon over leftwards harpoon end style BH+(aq) + OH−(aq)
Answer:
H+(aq) + B(aq) → BH+(aq)
Explanation:
When an acid is added onto a buffer, it is neutralized by the base.
So we pretty much have;
HCl + Weak base
Since HCl completely dissociates in water, it is represented as;
HCl(aq) --> H+(aq) + Cl-(aq)
The weak base reacts with the H+
So our Net ionic reaction is given as;
H+(aq) + B(aq) → BH+(aq)
Salad is a mixture because
the ingredients go
well together
the ingredients form
a pure substance
the ingredients are
not chemcically
combined
the ingredients are
chemically
combined
Answer:
are you asking if it's true or false?
Answer:
no
Explanation:
Calcium hydroxide, Ca(OH)2, is used as a calcium nutritional supplement in some foods and beverages, such as orange juice. What is the pH of a solution of 0.0012M calcium hydroxide at 25.0∘C?
Answer:
pH = 11.38
Explanation:
The pH of a solution is given as:
pH = pKw − pOH = 14.00 + log[OH-]
Since the concentration of Ca(OH)2 is 0.0012 M, the [OH−] is twice that, or 0.0024 M, resulting in pOH = 2.62 and pH = 11.38.
Final answer:
The pH of a solution of 0.0012M calcium hydroxide at 25.0°C is 11.38.
Explanation:
The pH of a solution of 0.0012M calcium hydroxide at 25.0°C can be calculated using the concentration of hydroxide ions ([OH-]).
Calcium hydroxide is a strong base that dissociates completely in water to form two hydroxide ions for every formula unit dissolved.
The concentration of the solute is 0.0012M, but because Ca(OH)2 is a strong base, the actual concentration of hydroxide ions ([OH-]) is two times this, or 2 × 0.0012M = 0.0024M.
Since [OH-] = 0.0024M, the pOH can be calculated as pOH = -log([OH-]) = -log(0.0024) = 2.62. The pH can then be calculated using the expression pH = 14 - pOH = 14 - 2.62 = 11.38.
Which of the following solutions is a good buffer system?Which of the following solutions is a good buffer system?A solution that is 0.10 M Li OH and 0.10 MHNO3A solution that is 0.10 MHCN and 0.10 MLiCNA solution that is 0.10 MNaCl and 0.10 MHClA solution that is 0.10 M Li and 0.10 MHNO3A solution that is 0.10 MHCN and 0.10 M Li Cl
Answer:
A solution that is 0.10 M HCN and 0.10 M LiCN.
Explanation:
A buffer solution is a solution of a weak acid and its conjugate base or a solution of a weak base and its conjugate acid, so the pH of the solution changes in a very little range when an acid or base is added to the solution.
Let's evaluate each statement:
(a) A solution that is 0.10 M LiOH and 0.10 M HNO₃
This is not a buffer solution since the HNO₃ is not the acid conjugate of the LiOH, and also, the LiOH is a strong base and the HNO₃ is a strong acid.
(b) A solution that is 0.10 M HCN and 0.10 M LiCN
This is a buffer solution, with the following reaction:
HCN + H₂O ⇄ CN⁻Li⁺ + H₃O⁺
The acid HCN is a weak acid and the LiCN is its conjugate base. The fact that the concentrations are equal for both is appropriate for the buffer solution.
(c) A solution that is 0.10 M NaCl and 0.10 M HCl
This is not a buffer solution since the HCl is a strong acid. It dissociates in water to form Cl⁻ and H⁺.
(d) A solution that is 0.10 M Li and 0.10 M HNO₃
This is not a buffer solution since the HNO₃ is not the conjugate base of Li, the HNO₃ is a strong acid that dissociates in water to form H⁺ and NO₃⁻.
(e) A solution that is 0.10 M HCN and 0.10 M LiCl
This is not a buffer solution since the LiCl is not the conjugate base of the acid HCN.
Therefore, the correct option is: A solution that is 0.10 M HCN and 0.10 M LiCN.
I hope it helps you!
Write a balanced net ionic equation to show why the solubility of Cu(OH)2(s) increases in the presence of a strong acid and calculate the equilibrium constant for the reaction of this sparingly soluble salt with acid. Use the pull-down boxes to specify states such as (aq) or (s).
The solubility of Cu(OH)2(s) increases in the presence of a strong acid due to the dissolution of the salt and formation of Cu2+ ions and water. The balanced net ionic equation for this process is Cu(OH)2(s) + 2H+(aq) → Cu2+(aq) + 2H2O(l). The equilibrium constant (K) for the reaction can be calculated using the concentrations of the reactants and products at equilibrium.
Explanation:The balanced net ionic equation to show why the solubility of Cu(OH)2(s) increases in the presence of a strong acid is:
Cu(OH)2(s) + 2H+(aq) → Cu2+(aq) + 2H2O(l)
Cu(OH)2 is a sparingly soluble salt, meaning it has low solubility in water. However, in the presence of a strong acid, the concentration of H+ ions increases, leading to the dissolution of Cu(OH)2 and the formation of Cu2+ ions and water.
The equilibrium constant for this reaction can be calculated by using the concentrations of the reactants and products at equilibrium. The equation for calculating the equilibrium constant (K) is:
K = [Cu2+][H2O2]/[Cu(OH)2][H+]2
Note: The square brackets indicate the concentrations of the species in the solution.
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17. Of the four different substances, which of the following has the highest alkalinity?
Substance A pH = 1.0
Substance B pH = 3.0
Substance C pH = 7.0
Substance D pH = 12.0 *
Answer:
Explanation:
Substance A
The reaction: 2 ClO2 (aq) + 2OH- (aq)→ ClO3- (aq) + ClO2- + H2O (l) was studied with the following results: Experiment [ClO2] (M) [OH-] (M) Initial Rate (M/s) 1 0.060 0.030 0.0248 2 0.020 0.030 0.00276 3 0.020 0.090 0.00828 a. Determine the rate law for the reaction. b. Calculate the value of the rate constant with the proper units. c. Calculate the rate when [ClO2] = 0.100 M and [OH-] = 0.050 M.
Answer:
Explanation:
question solved.
The rate law is defined as the rate of a chemical reaction, which is dependent on the concentration of the reactants.
It can be calculated by the formula:
[tex]\text v_o &= \text k [\text A]^x [\text B]^y[/tex]
where,
Vo = ratek = rate constantA = concentration of species Ax = order of reaction with respect to AB = concentration of species By = order of reaction with respect to BIn the given reaction:
[tex]\begin{aligned}2\;\text{ClO}_2\left(aq \right )+2\text{OH}^-\left(aq \right )\rightarrow\text{ClO}_3^-\left(aq \right )+\text{ClO}_2^-+\text{H}_2\text{O} \end{aligned}[/tex]
Using the rate law formula, we get:
Rate = K [Cl]ⁿ [OH⁻]ⁿ
0.0248 = K [0.060]ⁿ [0.030 ]ⁿ ........(1)
0.00276 = K [0.020]ⁿ [0.030 ]ⁿ .........(2)
0.00828 = K [0.020]ⁿ [0.090]ⁿ ..........(3)
Dividing (1) equation by (2), we get:
[tex]\begin {aligned} \dfrac {0.0248}{0.00276}&= \dfrac{\text K (0.06)^n (0.03)^n} {\text K (0.02)^n (0.03)^n}\\\\9 &= \dfrac{0.06}{0.02}^n\\\\3 ^2 &= 3 ^ m\\\text m &=2\\\end {aligned}[/tex]
Dividing the equation (2) by (3), we get:
[tex]\begin {aligned} \dfrac {0.00276}{0.00828 }&= \dfrac{\text K (0.02)^n (0.03)^n} {\text K (0.02)^n (0.09)^n}\\\\\dfrac{1}{3} &= \dfrac{0.03}{0.09}^n\\\\ \dfrac{1}{3} ^1 &= \dfrac{1}{3} ^n\\\\\text n &=2\\\end {aligned}[/tex]
Based on the rate law:
a. Rate = K [ClO₂]²⁻ [OH⁻]¹
b. 0.0248 = K [0.06]² [0.03]¹
K = [tex]\dfrac {0.0248}{(0.06)^2 \times 0.03}[/tex] = 229.63 m⁻²s⁻¹
c. Rate = K [ClO]₂ [OH⁻]ⁿ
Rate = 229.62 x (0.2)² (0.05)¹
Therefore, the rate of the reaction is 0.45926 m/sec.
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