Calculate the amount of work done against an atmospheric pressure of 1.00 atm when 500.0 g of zinc dissolves in excess acid at 30.0°C. Zn(s) + 2H+ (aq) → Zn2+(aq) + H2(g) Assume the volume of reactants is negligible compared to that of the vapor produced.

Answer : The final concentration of KOH, HF and KF are 0 M, 1.0 M and 1.0 M respectively.

Explanation :

The given chemical reaction is:

                      [tex]HF(aq)+KOH(aq)\rightarrow KF(aq)+H_2O(l)[/tex]

Initial conc.   2.0 M       1.0 M            0 M

Final conc.    1.0 M         0 M             1.0 M

When 1.0 M of KOH react with 2.0 M HF  then 1.0 M KOH will react with 1.0 M HF to form 1.0 M KF and 1.0 M HF remain unreacted.

So, the final solution contains 1.0 M HF and 1.0 M KF that means the solution contains equal amount of weak acid and salt.

Therefore, the final concentration of KOH, HF and KF are 0 M, 1.0 M and 1.0 M respectively.

The final concentration of KOH, HF and KF are 0 M, 1.0 M and 1.0 M respectively.

HF ( aq ) + KOH ( aq ) ⟶ KF ( aq ) + H₂O ( l )

Initial conc.   2.0 M       1.0 M            0 M

Final conc.    1.0 M         0 M             1.0 M

When 1.0 M of KOH react with 2.0 M HF then 1.0 M KOH will react with 1.0 M HF to form 1.0 M KF and 1.0 M HF remain unreacted. So, the final solution contains 1.0 M HF and 1.0 M KF that means the solution contains equal amount of weak acid and salt.

Therefore, the final concentration of KOH, HF and KF are 0 M, 1.0 M and 1.0 M respectively.

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B

Carbon has 4 valence electrons that can be involved in the formation of a covalent bond. This is why it can form various types of bonds with itself or other elements. Depending on the number of valence electrons involved in the binding, the bond can be a single, double or triple bond.

Explanation:

Remember the atoms sharing electrons in a covalent bond are aimed at achieving stable electron configuration. Carbon (2.4) being in the middle of the 2nd period seeks to be either 2 or 2.8.

This is why carbon based structures can vary so much due to the large variability in which the carbon atoms can bond. Remember carbon is the same element that forms graphite, diamond, and coal.

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Answer:

For Kp = 1,4; [tex]P_{[A] = 0,22[/tex], [tex]P_{[B] = 0,56atm[/tex]

For Kp = 2,0x10⁻⁴; [tex]P_{[A] = 0,495[/tex], [tex]P_{[B] = 0,01atm[/tex]

For Kp = 2,0x10⁵; [tex]P_{[A] = 5x10^{-6}[/tex], [tex]P_{[B] = 0,99999atm[/tex]

Explanation:

For the reaction:

A(g) ⇄ 2B(g)

kp is: [tex]kp = \frac{P_{[B]}^2}{P_{[A]}}[/tex]

If initial pressure of B is 1,0atm and initial pressure of A is 0,0atm the equilibrium pressures are:

[tex]P_{[A] = 0,0atm + X[/tex]

[tex]P_{[B] = 1,0atm - 2X[/tex]

Replacing for Kp= 1,4:

[tex]1,4 = \frac{(1-2X)^2}{X}[/tex]

1,4X = 4X² - 4X + 1

0 = 4X² - 5,4X + 1

Solving for X:

X = 0,22 -Right answer-

X = 1,13

Replacing:

[tex]P_{[A] = 0,22[/tex]

[tex]P_{[B] = 1,0atm - 0,44atm = 0,56atm[/tex]

For Kp= 2,0x10⁻⁴:

[tex]2,0x10^{-4} = \frac{(1-2X)^2}{X}[/tex]

2,0x10^{-4}X = 4X² - 4X + 1

0 = 4X² - 4,0002X + 1

Solving for X:

X = 0,495atm

Replacing:

[tex]P_{[A] = 0,495atm[/tex]

[tex]P_{[B] = 1,0atm - 0,99atm = 0,01atm[/tex]

For Kp= 2,0x10⁵:

[tex]2,0x10^5 = \frac{(1-2X)^2}{X}[/tex]

2,0x10^5X = 4X² - 4X + 1

0 = 4X² - 2,00004x10^5X + 1

Solving for X:

X = 5x10⁻⁶ -Right answer-

Replacing:

[tex]P_{[A] = 5x10^{-6}[/tex]

[tex]P_{[B] = 1,0atm - 0,00001atm = 0,99999atm[/tex]

I hope it helps!

To determine the equilibrium partial pressures of A and B for the given reaction, one must solve a quadratic equation derived from the equilibrium expression involving the given Kp and initial conditions, considering the stoichiometry and the relationship between the changes in partial pressures of A and B as the reaction reaches equilibrium.

When considering the equilibrium partial pressures of A and B for the reaction A(g) = 2B(g), we need to calculate how the initial conditions and the equilibrium constant (Kp) affect the final partial pressures at equilibrium. Starting with an initial partial pressure of B as 1.0 atm and A as 0.0 atm, and using the equilibrium expression Kp = (PB)^2/PA, we can plug in different values of Kp to solve for the unknowns. Assuming the reaction has proceeded to equilibrium, we can express any changes in partial pressure of A as -x and of B as +2x because for each mole of A reacting, 2 moles of B are formed.

For example, with Kp = 1.4, let's assume 'x' is the change in partial pressure of B; we then construct the equation Kp = (1 + 2x)^2/(0.0 + x). Solving the quadratic equation derived would give us the value of 'x', which in turn provides the equilibrium partial pressures PA and PB. We would need to solve a similar quadratic equation for different values of Kp such as 2.0 * 10^-4 and 2.0 * 10^5 following the same approach. It's important to note that some values might yield non-physical solutions, like negative pressures; those are dismissed since partial pressures must be positive.

Answer:

Option 4 is not the characteristics of esters

Explanation:

Esters :

They are organic compound derived from an organic or inorganic acid. in which one Hydroxyl (OH) group is replaced by an organic alkoxy (-O-R) group.

General formula of Esters:

Easter can be represented by a general formula that is

                                       RCOOR

where R is any alkyl group

No to look at the characteristics of the Esters an find out the odd one option that is not correct.

Option 1 is the characteristics of esters.

Esters are obtained from the reaction of carboxylic acid and an alcohol.

          CH₃COOH + CH₃OH -------------> CH₃COOCH₃ + H₂O

Option 2 is the characteristics of esters.

This option is also correct as if we see at its general formula

The carbonyl group attached to an Oxygen atom and this oxygen is attached to carbon of alkyl group

                                  O==C------OR

Option 3 is also the characteristics of esters

The odors and flavors of many flowers, perfumes, and ripe fruits is due to the presence of ester. as ester have now hydrogen bonding and low vapor pressure and highly volatile that's why it is responsible for odors.

Option 4 is not the characteristics of esters

This option is wrong, as the carbon atom in the middle of the carbon chain can not be easy to replace, also the carbonyl carbon is directly attached to oxygen group and not Carbon group.                    

Answer:

The balanced reaction is:-

[tex]C_6H_5COO^-_{(aq)} + H_2O_{(l)}\rightleftharpoons C_6H_5COOH_{(aq)} + OH^-_{(aq)}[/tex]

[tex]K_b[/tex] expression is:-

[tex]K_{b}=\frac {\left [ C_6H_5COOH \right ]\left [ {OH}^- \right ]}{[C_6H_5COO^-]}[/tex]

Explanation:

Benzoate ion is the conjugate base of the benzoic acid. It is a Bronsted-Lowry base and the dissociation of benzoate ion can be shown as:-

[tex]C_6H_5COO^-_{(aq)} + H_2O_{(l)}\rightleftharpoons C_6H_5COOH_{(aq)} + OH^-_{(aq)}[/tex]

The expression for dissociation constant of benzoate ion is:

[tex]K_{b}=\frac {\left [ C_6H_5COOH \right ]\left [ {OH}^- \right ]}{[C_6H_5COO^-]}[/tex]

Final answer:

The balanced chemical equation for the reaction of benzoate ion, C6H5COO−, in water is C6H5COO−(aq) + H2O(l) ⇌ C6H5COOH(aq) + OH−(aq), and the Kb expression is Kb = [C6H5COOH][OH−] / [C6H5COO−].

Explanation:

The question involves writing a balanced equation for the reaction of the benzoate ion, C6H5COO−, as a Brønsted-Lowry base in water, and then writing the Kb expression for the reaction. In water, the benzoate ion accepts a proton (H+) from water (‘H2O’), forming benzoic acid (C6H5COOH) and hydroxide ions (OH−). The balanced chemical reaction is as follows:

C6H5COO−(aq) + H2O(l) ⇌ C6H5COOH(aq) + OH−(aq)

The Kb expression, which represents the base ionization constant, is written without including the states of the substances. It is derived from the concentrations of the products over the concentration of the reactant, not including water due to its constant concentration in dilute solutions. The Kb expression is:

Kb = [C6H5COOH][OH−] / [C6H5COO−]

In "condensed structural formula" each carbon atom and its attached hydrogen atoms are written in group in the linear form is correct about organic chemistry.

Option B

Explanation:

"condensed structural formula" is a method of writing or presenting organic structures in line of text. It presents all the atoms, but excludes the vertical bonds and all the horizontal single bonds. In condensed structural formula, or we can say semi-structural formula, covalent bonds are not always presented or shown. When the formula or representation is written in line with covalent bonds being shown, then it is referred to as linear formula. For example- the condensed structural formulas of ethane, propane, and ethanol is written as follows:-  

[tex]\mathrm{CH}_{3} \mathrm{CH}_{3},\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{3},\text { and } \mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{OH}[/tex]

Apart from these Statement, all others are false because they do not have any logic with respect to organic chemistry.

The correct statement about organic chemistry is:  Alkanes are a type of organic compound that have at least one multiple bond between two carbon atoms.

The correct answer is option C.

a. Organic compounds typically contain carbon and hydrogen, but they can also include other elements like oxygen, nitrogen, sulfur, and more. So, the word "only" in this statement is incorrect.

b. In a condensed structural formula, each carbon atom and its attached hydrogen atoms are typically written as a group, but the arrangement isn't necessarily linear. It represents a simplified way to depict the structure of organic compounds, but the linear form is not a strict requirement. The statement is generally correct but could be misleading due to the term "linear."

c. Alkanes are a type of organic compound that consists of single bonds between carbon atoms, not multiple bonds. The statement is correct.

d. Conformations in organic chemistry refer to the different three-dimensional arrangements of atoms or groups around single bonds, such as in alkanes. The statement is incorrect because it mistakenly refers to the "double bond," which is not characteristic of alkanes.

In summary, statement (c) is the correct one. Alkanes are indeed organic compounds with only single bonds between carbon atoms. The other statements have minor inaccuracies or incorrect terms that make them less precise or entirely incorrect.

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Answer : The amount of heat required is, 639.3 KJ

Solution :

The conversions involved in this process are :

[tex](1):Cr(s)(1760^oC)\rightarrow Cr(s)(1860^oC)\\\\(2):Cr(s)(1860^oC)\rightarrow Cr(l)(1860^oC)\\\\(3):Cr(l)(1860^oC)\rightarrow Cr(l)(2060^oC)[/tex]

Now we have to calculate the enthalpy change.

[tex]\Delta H=[m\times c_{p,s}\times (T_{final}-T_{initial})]+n\times \Delta H_{fusion}+[m\times c_{p,l}\times (T_{final}-T_{initial})][/tex]

where,

[tex]\Delta H[/tex] = enthalpy change or heat required = ?

m = mass of Cr = 126.3 g

[tex]c_{p,s}[/tex] = specific heat of solid Cr = [tex]44.8J/g^oC[/tex]

[tex]c_{p,l}[/tex] = specific heat of liquid Cr = [tex]0.94J/g^oC[/tex]

n = number of moles of Cr = [tex]\frac{\text{Mass of Cr}}{\text{Molar mass of Cr}}=\frac{126.3g}{52g/mole}=2.428mole[/tex]

[tex]\Delta H_{fusion}[/tex] = enthalpy change for fusion = 20.5 KJ/mole = 20500 J/mole

Now put all the given values in the above expression, we get

[tex]\Delta H=[126.3g\times 44.8J/g^oC\times (1860-(1760))^oC]+2.428mole\times 20500J/mole+[126.3g\times 0.94J/g^oC\times (2060-1860)^oC][/tex]

[tex]\Delta H=639342.4J=639.3KJ[/tex]     (1 KJ = 1000 J)

Therefore, the amount of heat required is, 639.3 KJ

To determine the amounts of heat for each heating step, we need to calculate the heat required to raise the temperature from solid Cr at 1760°C to its melting point at 1860°C, the heat of fusion to convert the solid Cr at its melting point to liquid Cr, and the heat required to raise the temperature from liquid Cr at 1860°C to the final temperature of 2060°C.

To determine the amounts of heat for each heating step, we need to calculate the heat required to raise the temperature from solid Cr at 1760°C to its melting point at 1860°C, the heat of fusion to convert the solid Cr at its melting point to liquid Cr, and the heat required to raise the temperature from liquid Cr at 1860°C to the final temperature of 2060°C.

By summing up the heats calculated in each step, you can determine the total amount of heat required to convert the given mass of solid Cr at 1760°C to liquid Cr at 2060°C.

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Answer:

a) f = 3.02x10¹⁵ s⁻¹, and λ = 99.4 nm.

b) 99.4 nm

Explanation:

a) The energy of radiation is given by:

E = h*f

Where h is the Planck constant (6.626x10⁻³⁴ J.s), and f is the frequency. To have the highest frequency, the energy must be the highest too, because they're directly proportional. So we must use E = -E1 = 20x10⁻¹⁹ J

20x10⁻¹⁹ = 6.626x10⁻³⁴xf

f = 3.02x10¹⁵ s⁻¹

The wavelenght is the velocity of light (3.00x10⁸ m/s) divided by the frequency:

λ = 3.00x10⁸/3.02x10¹⁵

λ = 9.94x10⁻⁸ m = 99.4 nm

b) To have the shortest wavelength, it must be the highest energy and frequency, so it would be the same as the letter a) 99.4 nm.

Answer: The Gibbs free energy of the reaction is -8.82 kJ/mol

Explanation:

The equation used to Gibbs free energy of the reaction follows:

[tex]\Delta G=\Delta G^o+RT\ln K_{eq}[/tex]

where,

[tex]\Delta G[/tex] = free energy of the reaction

[tex]\Delta G^o[/tex] = standard Gibbs free energy = -16.7 kJ/mol = -16700 J/mol  (Conversion factor: 1kJ = 1000J)

R = Gas constant = [tex]8.314J/K mol[/tex]

T = Temperature = [tex]37^oC=[273+37]K=310K[/tex]

[tex]K_{eq}[/tex] = Ratio of concentration of products and reactants = 21.3

Putting values in above equation, we get:

[tex]\Delta G=-16700J/mol+(8.314J/K.mol\times 310K\times \ln (21.3))\\\\\Delta G=-8816.7J/mol=-8.82kJ/mol[/tex]

Hence, the Gibbs free energy of the reaction is -8.82 kJ/mol

Answer:

X is the chemical symbol of the element.

A is the mass number (number of protons neutrons).

Z is the atomic number (number of protons).

Explanation:

In stating the chemical representation of an element, the AZX symbol is used.

The symbol of the element may either come from its Latin or English name. For instance, the symbol of the element sodium, comes from its Latin name natrium (Na).

Its atomic number is the number of protons in the nucleus of the atom. For sodium, the atomic number is 11.

The mass number refers to the sum of the number of protons and neutrons in the atom. For sodium the mass number is 23.

Hence the AZX symbol for sodium is

23_11Na.

The correct option as regarding the definition of A, Z and X in ᴬ₂X are:

Nuclide of elements are generally represented according to the following notation:

ᴬ₂X

Where

With the above information, we can determine the options that is correct from the question.

Thus, the correct options are:

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Answer:

The correct option is: C. form stable hydrogen-bonded dimers

Explanation:

Boiling point is the temperature at which a particular substance changes from liquid state to vapor state.

The boiling point of a chemical substance depends upon the intermolecular forces present between the molecules.

Carboxylic acids are the organic molecules containing carboxyl functional group (COOH). They tend to have greater boiling point than alcohols, ketones, or aldehydes.

This is because only carboxylic acids are capable of forming dimers that are stabilized by hydrogen bonding.

Answer:

8.3 kJ

Explanation:

In this problem we have to consider that both water and the calorimeter absorb the heat of combustion, so we will calculate them:

q for water:

q H₂O = m x c x ΔT where m: mass of water = 944 mL x 1 g/mL = 944 g

                                      c: specific heat of water = 4.186 J/gºC

                                     ΔT : change in temperature = 2.06 ºC

so solving for q :

q H₂O = 944 g x 4.186 J/gºC x 2.06 ºC = 8,140 J

For calorimeter

q calorimeter  = C x  ΔT  where C: heat capacity of calorimeter = 69.6 ºC

                                     ΔT : change in temperature = 2.06 ºC

q calorimeter = 69.60J x 2.06 ºC = 143.4 J

Total heat released = 8,140 J +  143.4 J = 8,2836 J

Converting into kilojoules by dividing by 1000 we will have answered the question:

8,2836 J x 1 kJ/J = 8.3 kJ

The heat produced by the combustion of 1.98g of the hydrocarbon is 0.143 kJ.

The volume of water was not needed for this particular calculation.

Where:

Given:

Let's plug in the values:

The complexes are sodium hexachloroplatinate(IV), potassium trisoxalatoferrate(III), and pentaamminechlorocobalt(III) chloride.

(a) There are two Na+ ions, so the coordination sphere has a negative two charge: [PtCl6]². There are six anionic chloride ligands, so -2 = -6 + x, and the oxidation state of the platinum is 4+. The name of the complex is sodium hexachloroplatinate(IV), and the coordination number is six.

(b) The coordination sphere has a charge of 3- (based on the potassium) and the oxalate ligands each have a charge of 2-, so the metal oxidation state is given by -3 = -6+ x, and this is an iron(III) complex. The name is potassium trisoxalatoferrate(III) (note that tris is used instead of tri because the ligand name starts with a vowel). Because oxalate is a bidentate ligand, this complex has a coordination number of six.

(c) In this example, the coordination sphere has a cationic charge of 2+. The NH3 ligand is neutral, but the chloro ligand has a charge of 1-. The oxidation state is found by +2 = -1 + x and is 3+, so the complex is pentaamminechlorocobalt(III) chloride and the coordination number is six.

Answer:

C.) At room temperature and pressure, because intermolecular interactions are minimized and the particles are relatively far apart.

Explanation:

For gas to behave as an ideal gas there are 2 basic assumptions:

In which instance is a gas most likely to behave as an ideal gas?

A.) At low temperatures, because the molecules are always far apart. FALSE. At low temperatures, molecules are closer and IMF are more appreciable.

B.) When the molecules are highly polar, because IMF are more likely. FALSE. When IMF are stronger the gas does not behave as an ideal gas.

C.) At room temperature and pressure, because intermolecular interactions are minimized and the particles are relatively far apart. TRUE.

D.) At high pressures, because the distance between molecules is likely to be small in relation to the size of the molecules. FALSE. At high pressures, the distance between molecules is small and IMF are strong.

Answer:

The correct answer is a  coenzyme cosubstrate is loosely bound to an enzyme and dissociates in an altered form as the part of the catalytic cycle.Its original form is regenerated not by the cycle but by other enzyme.

Explanation:

The  prosthetic group of the enzyme pyruvate dehydrogenase is

2 TPP or Thymine pyrophosphate.

3  Lipomide.

Answer:

D.) The higher vapor pressure of acetone results in more rapid evaporation and heat loss

Explanation:

Acetone being liquid with very low boiling point and hence can be easily be converted to gaseous state .

And ,

Therefore have higher vapour pressure and as liquid gets converted to gas , the process of evaporation takes place and leads to loss of heat .

Hence , from the given options , the most appropriate option according to given statement of the question is ( d ) .

The cooling sensation felt with acetone is due to its rapid evaporation, which absorbs heat from the skin. This occurs because acetone has a higher vapor pressure and weaker intermolecular forces compared to water. Option D is the correct option.

The phenomenon observed by the student can be explained by the fact that acetone evaporates more rapidly than water. This rapid evaporation leads to a cooling effect because evaporation is an endothermic process that absorbs heat from the surroundings. Option D is the correct explanation: The higher vapor pressure of acetone results in more rapid evaporation and heat loss.

Acetone has weaker intermolecular forces compared to water, primarily dipole-dipole interactions rather than hydrogen bonds. This means acetone molecules can escape into the gas phase much more easily. When acetone evaporates, it requires energy, which it absorbs from the surroundings, leading to a cooling sensation on the skin.

Answer : The enthalpy of combustion per mole of [tex]C_6H_{12}O_6[/tex] is -2815.8 kJ/mol

Explanation :

Enthalpy change : It is defined as the difference in enthalpies of all the product and the reactants each multiplied with their respective number of moles. It is represented as [tex]\Delta H^o[/tex]

The equation used to calculate enthalpy change is of a reaction is:  

[tex]\Delta H^o_{rxn}=\sum [n\times \Delta H^o_f(product)]-\sum [n\times \Delta H^o_f(reactant)][/tex]

The equilibrium reaction follows:

[tex]C_6H_{12}O_6(s)+6O_2(g)\rightleftharpoons 6CO_2(g)+6H_2O(l)[/tex]

The equation for the enthalpy change of the above reaction is:

[tex]\Delta H^o_{rxn}=[(n_{(CO_2)}\times \Delta H^o_f_{(CO_2)})+(n_{(H_2O)}\times \Delta H^o_f_{(H_2O)})]-[(n_{(C_6H_{12}O_6)}\times \Delta H^o_f_{(C_6H_{12}O_6)})+(n_{(O_2)}\times \Delta H^o_f_{(O_2)})][/tex]

We are given:

[tex]\Delta H^o_f_{(C_6H_{12}O_6(s))}=-1260kJ/mol\\\Delta H^o_f_{(O_2(g))}=0kJ/mol\\\Delta H^o_f_{(CO_2(g))}=-393.5kJ/mol\\\Delta H^o_f_{(H_2O(l))}=-285.8kJ/mol[/tex]

Putting values in above equation, we get:

[tex]\Delta H^o_{rxn}=[(6\times -393.5)+(6\times -285.8)]-[(1\times -1260)+(6\times 0)]=-2815.8kJ/mol[/tex]

Therefore, the enthalpy of combustion per mole of [tex]C_6H_{12}O_6[/tex] is -2815.8 kJ/mol

Answer:

muahhh

Explanation:

Answer:

(a) Cgas = 0.125 kJ/k

(b) cgas = 0.25kJ/kg.K

(c) cm(gas) = 0.021kJ/mol.K

Explanation:

18.9 kJ is equal to the sum of the heat absorbed by the gas and the heat absorbed by the calorimeter.

Qcal + Qgas = 18.9 kJ  [1]

We can calculate the heat absorbed using the following expression.

Q = C . ΔT

where,

C is the heat capacity

ΔT is the change in the temperature

(a) What is the heat capacity of the sample?

From [1],

Ccal . ΔT + Cgas . ΔT = 18.9 kJ

(2.22kJ/K) × 8.06 K + Cgas × 8.06 K = 18.9 kJ

Cgas = 0.125 kJ/k

(b) If the sample has a mass of 0.5 kilograms, what is the specific heat capacity of the substance?

We can calculate the specific heat capacity (c) using the following expression:

[tex]c=\frac{C}{m} =\frac{0.125kJ/K}{0.5kg} =0.25kJ/kg.K[/tex]

(c) If the sample is Krypton, what is the molar heat capacity at constant volume of Krypton? The molar mass of Krypton is 83.8 grams/mole.

The molar heat capacity is:

[tex]\frac{0.25kJ}{kg.K} .\frac{1kg}{1000g} .\frac{83.8g}{mol} =0.021kJ/mol.K[/tex]

Final answer:

The heat capacity of the sample is 2.34 kJ/K. The specific heat capacity of the substance is 4.68 kJ/(kg*K). The molar heat capacity at constant volume of Krypton is 0.0559 kJ/(mol*K).

Explanation:

The heat capacity of a substance is the amount of energy required to increase its temperature by 1 degree. The specific heat capacity is the amount of energy required to increase the temperature of 1 gram of a substance by 1 degree.

(a) To find the heat capacity of the sample, we can use the equation Q = CΔT, where Q is the amount of heat transferred, ΔT is the change in temperature, and C is the heat capacity. Rearranging the equation, C = Q/ΔT. Plugging in the given values, C = 18.9 kJ / 8.06 K

= 2.34 kJ/K.

(b) To find the specific heat capacity of the substance, we need to know the mass of the sample. Given that the mass is 0.5 kilograms, we can use the equation cs = C/m, where cs is the specific heat capacity, C is the heat capacity, and m is the mass. Plugging in the values, cs = 2.34 kJ/K / 0.5 kg

= 4.68 kJ/(kg*K).

(c) To find the molar heat capacity at constant volume of Krypton, we can use the equation Cm = cs / M, where Cm is the molar heat capacity, cs is the specific heat capacity, and M is the molar mass. Plugging in the values, Cm = 4.68 kJ/(kg*K) / 83.8 g/mol

= 0.0559 kJ/(mol*K).

Answer:

[tex]150~ppm[/tex]

Explanation:

The first step is to draw the ionization reaction of [tex]NaNO_2[/tex], so:

[tex]NaNO_2~->~Na^+~+~NO_2^-[/tex]

The molar ratio between [tex]NaNO_2[/tex] and [tex]NO_2^-[/tex] is 1:1

The next step is the calculation of the concentration. We have to remember that the formula of ppm is:

[tex]ppm=\frac{mg}{L}[/tex]

In this case we will have a mass of 150 mg and a volume of 1 L so:

[tex]ppm=\frac{150~mg}{1~L}=~150ppm[/tex]

Answer:

The correct answer is C fatty acid oxidation would stop when all of the CoA is bound as acetyl CoA.

Explanation:

Acetyl CoA is the principle end product of beta oxidation of even chain fatty acid such as palmitic acid.

    When the cellelar label of actyl CoA increases at that time the excess acetyl CoA is converted to ketone bodies by the process called ketogenesis.

 According to the question if the excess acetyl CoA is not converted to ketone bodies then it will interfere with the oxidation of fatty acid because fatty acid molecules will not get any CoA SH molecule to activate themselves to initiate a new round of beta oxidation.

As a result fatty acid oxidation will stop.

Answer:

C. Fatty acid oxidation would stop when all of the CoA is bound as acetyl‑CoA.

Explanation:

Hello,

In this case, due to the fact that the mitochondrial pool of the CoA is short, thus, such cofactor must be recycled from acetyl-CoA through the production of ketone-like bodies. Therefore, the operation of the beta-oxidation pathway is performed, as it is necessary for energy production, in such a way one concludes that fatty acid oxidation would stop when all of the CoA is bound as acetyl‑CoA.

Best regards.

Answer:

Is not possible to make a buffer near of 7.

Optimal pH for sulfate‑based buffers is 2.

Explanation:

The dissociations of H₂SO₄ are:

H₂SO₄ ⇄ H⁺ + HSO₄⁻ pka₁ = -10

HSO₄⁻ ⇄ H⁺ + SO₄²⁻ pka₂ = 2.

The buffering capacity is pka±1. That means that for H₂SO₄ the buffering capacity is in pH's between -11 and -9 and between 1 and 3, having in mind that pH's<0 are not useful. For that reason, is not possible to make a buffer near of 7.

The optimal pH for sulfate‑based buffers is when pka=pH, that means that optimal pH is 2.

I hope it helps!

Answer:

2.04 is the pOH of a 0.0092 M CsOH solution.

Explanation:

Molarity of cesium hydroxde = [CsOH]= 0.0092

[tex]CsOH(aq)\rightarrow Cs^+(aq)+OH^-(aq)[/tex]

1 mole of cesium hydroxide gives 1 mole of cesium ion and 1 mole of hydroxide ion.

Then 0.0092 M cesium hydroxide will give :

[tex][OH^-]=1\times [CsOH]=1\times 0.0092 M=0.0092M [/tex]

The pOH of the solution is the negative logarithm of concentration of  hydroxide ions in a solution.

[tex]pOH=-\log [OH^-][/tex]

[tex]pOH=-\log [0.0092 M]=2.0362\approx 2.04 [/tex]

2.04 is the pOH of a 0.0092 M CsOH solution.

Final answer:

The pOH of a 0.0092 [tex]M CsOH[/tex] solution is calculated using the negative log of the hydroxide ion concentration, which results in a pOH of 2.04. Thus, the correct answer is (A) 2.04.

Explanation:

The student is asking about how to calculate the pOH of a [tex]CsOH[/tex] solution. Since CsOH is a strong base, it will dissociate completely in water.

The concentration of hydroxide ions (OH-) in a 0.0092 [tex]M CsOH[/tex] solution will be the same as the concentration of CsOH itself, which is 0.0092 M.

To find the pOH, we take the negative logarithm (base 10) of the hydroxide ion concentration:

[tex]pOH = -log[OH-][/tex]
[tex]pOH = -log(0.0092)[/tex]
[tex]pOH = -(-2.036)[/tex]
[tex]pOH = 2.036[/tex]

Therefore, rounding to two decimal places, the pOH of a 0.0092 [tex]M CsOH[/tex] solution is 2.04. Hence, the correct answer is (A) 2.04.

the concentration of [tex]\(Sn^{2+}\)[/tex] is approximately [tex]\(3.3 \times 10^{-2} \, \text{M}\)[/tex].

To solve this problem, we can use the Nernst equation, which relates the cell potential [tex](\(E_{\text{cell}}\))[/tex] to the standard cell potential [tex](\(E^{\circ}_{\text{cell}}\))[/tex] and the concentrations of the species involved in the redox reaction:

[tex]\[ E_{\text{cell}} = E^{\circ}_{\text{cell}} - \frac{0.0592}{n} \log \left( \frac{[\text{cathode product}]^m}{[\text{anode product}]^n} \right) \][/tex]

Given the standard reduction potentials, we can determine that the number of electrons involved in the half-reactions is [tex]\(n = 2\)[/tex]. The given cell potential is [tex]\(E_{\text{cell}} = 0.660 \, \text{V}\)[/tex]. We need to find the concentration of [tex]\(Sn^{2+}\)[/tex].

First, let's write the Nernst equation for the given cell:

[tex]\[ 0.660 \, \text{V} = (E^{\circ}_{\text{cell}}) - \frac{0.0592}{2} \log \left( \frac{[\text{Sn}^{2+}]}{[\text{Zn}^{2+}]} \right) \][/tex]

We're given the standard reduction potentials, which are [tex]\(E^{\circ}_{\text{cell}} = -0.76 \, \text{V}\)[/tex] for the zinc half-reaction and [tex]\(E^{\circ}_{\text{cell}} = -0.136 \, \text{V}\)[/tex] for the tin half-reaction.

Plugging in the values and solving for [tex]\([\text{Sn}^{2+}]\)[/tex]:

[tex]\[ 0.660 \, \text{V} = (-0.76 \, \text{V}) - \frac{0.0592}{2} \log \left( \frac{[\text{Sn}^{2+}]}{2.5 \times 10^{-3}} \right) \][/tex]

[tex]\[ 0.660 \, \text{V} = (-0.76 \, \text{V}) - 0.0296 \log \left( \frac{[\text{Sn}^{2+}]}{2.5 \times 10^{-3}} \right) \][/tex]

[tex]\[ 0.660 + 0.76 = 0.0296 \log \left( \frac{[\text{Sn}^{2+}]}{2.5 \times 10^{-3}} \right) \][/tex]

[tex]\[ 0.0296 \log \left( \frac{[\text{Sn}^{2+}]}{2.5 \times 10^{-3}} \right) = 0.76 + 0.660 \][/tex]

[tex]\[ \log \left( \frac{[\text{Sn}^{2+}]}{2.5 \times 10^{-3}} \right) = \frac{1.42}{0.0296} \][/tex]

[tex]\[ \log \left( \frac{[\text{Sn}^{2+}]}{2.5 \times 10^{-3}} \right) = 47.973 \][/tex]

[tex]\[ \frac{[\text{Sn}^{2+}]}{2.5 \times 10^{-3}} = 10^{47.973} \][/tex]

[tex]\[ [\text{Sn}^{2+}] = (2.5 \times 10^{-3}) \times 10^{47.973} \][/tex]

[tex]\[ [\text{Sn}^{2+}] \approx 3.3 \times 10^{45} \, \text{M} \][/tex]

Therefore, the concentration of [tex]\(Sn^{2+}\)[/tex] is approximately [tex]\(3.3 \times 10^{-2} \, \text{M}\)[/tex].

Answer: The change in temperature is 84.7°C

Explanation:

To calculate the change in temperature, we use the equation:

[tex]q=mc\Delta T[/tex]

where,

q = heat absorbed = 1 kCal = 1000 Cal    (Conversion factor: 1 kCal = 1000 Cal)

m = mass of steel = 100 g

c = specific heat capacity of steel = 0.118 Cal/g.°C

[tex]\Delta T[/tex] = change in temperature = ?

Putting values in above equation, we get:

[tex]1000cal=100g\times 0.118cal/g^oC\times \Delta T\\\\\Delta T=\frac{1000cal}{100g\times 0.118cal/g^oC}\\\\\Delta T=84.7^oC[/tex]

Hence, the change in temperature is 84.7°C

Answer:

C.) Both substances are made up of nonpolar molecules

Explanation:

Bromine is soluble in mineral oil because both substances are made of nonpolar molecules.A solute is highly soluble in a solvent that has the same chemical structure as it has. Bromine is a diatomic molecule that has dipole moments that cancel out to form a non-polar molecular. Mineral oil contains Carbon atoms bonded to hydrogen atoms forming nonpolar molecules.

Answer:

4) Each cytochrome has an iron‑containing heme group that accepts electrons and then donates the electrons to a more electronegative substance.

Explanation:

The cytochromes are proteins that contain heme prosthetic groups. Cytochromes undergo oxidation and reduction through loss or gain of a single electron by the iron atom in the heme of the cytochrome:

[tex]Cytochrome-Fe²⁺ ⇄ cytochrome-Fe³⁺-e⁻[/tex]

The reduced form of ubiquinone (QH₂), an extraordinarily mobile transporter, transfers electrons to cytochrome reductase, a complex that contains cytochromes b and c₁, and a Fe-S center. This second complex reduces cytochrome c, a water-soluble membrane peripheral protein. Cytochrome c, like ubiquinone (Q), is a mobile electron transporter, which is transferred to cytochrome oxidase. This third complex contains the cytochromes a, a₃ and two copper ions. Heme iron and a copper ion of this oxidase transfer electrons to O₂, as the last acceptor, to form water.

Each transporter "downstream" is more electronegative than its neighbor "upstream"; oxygen is located in the inferior part of the chain. Thus, the electrons fall in an energetic gradient in the electron chain transport to a more stable localization in the electronegative oxygen atom.

Answer:

8.46

Explanation:

Atomic number : It is defined as the number of electrons or number of protons present in a neutral atom.

Also, atomic number of I = 549

Thus, the number of protons = 49

Mass number is the number of the entities present in the nucleus which is the equal to the sum of the number of protons and electrons.

Mass number = Number of protons + Number of neutrons

105 =  49 + Number of neutrons

Number of neutrons = 56

Mass of neutron = 1.008665 amu

Mass of proton = 1.007825 amu

Calculated mass = Number of protons*Mass of proton + Number of neutrons*Mass of neutron

Thus,

Calculated mass = (49*1.007825 + 56*1.008665) amu = 105.868665 amu

Mass defect = Δm = |105.868665 - 104.914558| amu = 0.954107 amu

The conversion of amu to MeV is shown below as:-

1 amu = 931.5 MeV

So, Energy = 0.954107*931.5 MeV/atom = 888.750671 MeV/atom

Also, 1 atom has 105 nucleons (Protons+neutrons)

So, Energy = 888.750671 MeV/105nucleons = 8.46 MeV/nucleon

Answer:- 8.46

The binding energy per nucleon for an atom of 105In is calculated by determining the mass defect, converting it to energy using Einstein's mass-energy equivalence, and dividing by the number of nucleons.

To calculate the binding energy per nucleon in MeV for an atom of 105In with a mass of 104.914558 amu, we must first identify the number of protons and neutrons in the nucleus. Indium-105 has 49 protons (since In is the element with atomic number 49), and subtracting this from the mass number 105 gives us 56 neutons. The mass of the protons is 49 x 1.007825 amu, and the mass of the neutrons is 56 x 1.008665 amu.

Next, we calculate the mass defect by subtracting the atomic mass of the 105In from the combined mass of the protons and neutrons. To convert the mass defect into energy, we multiply by 931.5 MeV/amu, according to Einstein’s mass-energy equivalence principle (E=mc2). Lastly, we divide this energy by the total number of nucleons (protons + neutrons) to find the binding energy per nucleon.

Answer:

ΔH of reaction is -856 kJ/mol

Explanation:

The property ΔH is property which can be added to find the net change in enthalpy of reaction.

ΔH of first reaction is -665.9 kJ/mol

ΔH of second reaction is 190.1 kJ/mol

carefully looking at the third equation,

it is first reaction - second reaction.

thus, by Hess's law,

Hess's Law of Constant Heat Summation (or just Hess's Law) states that regardless of the multiple stages or steps of a reaction, the total enthalpy change for the reaction is the sum of all changes.

ΔH of third reaction is = [tex]-665.9 - (190.1)[/tex]

ΔH =  -856 kJ/mol

Answer:

Explanation:ANd of course,

Δ

H

∘

f

=

0

for an element (here dixoygen) in its standard state

Answer:

a. ΔHr = 696,8 kJ/mol

b. ΔHr = -1164,7 kJ/mol

c. ΔHr = -467,9 kJ/mol

Explanation:

It is possible to obtain the standard enthalpy change of a reaction with the ΔH°f of products - ΔH°f reactants.

a. For the reaction:

N₂(g) + 3H₂O(l) → 2NH₃(aq) + ³/₂O₂(g)

ΔHr = 2ΔH°f NH₃(aq) + ³/₂ΔH°fO₂(g) - (3ΔH°fH₂O(l) + 2ΔH°f N₂(g))

ΔHr = 2×-80,3 kJ/mol + ³/₂×0 - (3×-285,8 kJ/mol + 0)

ΔHr = 696,8 kJ/mol

b. and c. For the reaction:

NH₃(aq) + 2CH₄(g) + ⁵/₂O₂(g) → NH₂CH₂COOH(s) + 3H₂O(l)

ΔHr = ΔH°fNH₂CH₂COOH(s) + 3ΔH°fH₂O(l) - (ΔH°fNH₃(aq) + 2ΔH°fCH₄(g) + ⁵/₂ΔH°fO₂(g))

ΔHr = -537,2kJ/mol + 3×-285,8 kJ/mol  - (-80,3 kJ/mol + 2×-74,8kJ/mol+ ⁵/₂×0)

ΔHr = -1164,7 kJ/mol

c. From nitrogen, methane and oxygen the reaction is the sum of reactions of a and b:

N₂(g) + 3H₂O(l) → 2NH₃(aq) + ³/₂O₂(g)

+ NH₃(aq) + 2CH₄(g) + ⁵/₂O₂(g) → NH₂CH₂COOH(s) + 3H₂O(l)

N₂(g) + 2CH₄(g) + O₂(g) → NH₂CH₂COOH(s) + NH₃(aq)

By Hess's law, the ΔHr will be the sum of the ΔHr of the last two reactions, that means:

ΔHr = -1164,7 kJ/mol + 696.8 kJ/mol

ΔHr = -467,9 kJ/mol

I hope it helps!

Answer:

From Molarity=concentration/molar mass

Concentration=10/0.3dm³

33.33g/dm³

Molar mass=H2O=18g/mol

Molarity=1.852mol/dm³

Answer:

0. 446 mol L−1

Explanation:

For Molarity, we must know the following things  

• the number of moles of solute present in solution

• the total volume of the solution

we know the mass of one mole of potassium chloride = 74.55 g  

Number of moles = Given Mass of substance / Mass of one mole

No of moles = 10 / 74.55

                   = 0.134 moles  

Now we know that  molarity is expressed per liter of solution. Since you dissolve 0.134 moles of potassium chloride in 300. mL of solution, you can say that 1.0 L will contain

For 300 ml of solution, no of moles are = 0.134 moles

For 1 ml of solution, no of moles are = 0.134/300 moles

For 1(1000) ml of solution, no of moles are=  0.134/300 x 1000

                                                                 = 0.446 moles/ L

Answer is =0. 446 mol L−1