What is true about a car with constant velocity? (Select all that apply)
A. It maintains the same speed
B. It continues in the same direction
C. There is a decrease in speed
D. It has a negative acceleration Answer, it has a positive acceleration
E. It has zero acceleration
F. It has a changing direction

The molarity is 0.67 M

Molarity is a measure of concentration used in chemistry. It is defined as the number of moles of a solute dissolved in one liter of solution. The unit of molarity is moles per liter (mol/L) or sometimes expressed as M.

Molarity is a useful way to express the concentration of a solution because it is easy to measure the volume of a solution and the amount of solute dissolved in it.

Using the dilution formula;

C1V1= C2V2

C2 = C1V1/V2

=  1.75M * 25.0 mL/65.0 mL

= 0.67 M

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a.The heat of reaction for each step in the free-radical bromination of methane is kJ/mol = -138.8 kJ/mol.

b.The overall heat of reaction is -40.3 kJ/mol

(a) The heat of reaction for each step in the free-radical bromination of methane can be calculated using the bond-dissociation enthalpies from Table 4-2.

For the first step, the heat of reaction is equal to the sum of the bond-dissociation enthalpies of Br2 and CH4, which is -104.2 kJ/mol + -74.9 kJ/mol = -179.1 kJ/mol.

For the second step, the heat of reaction is equal to the sum of the bond-dissociation enthalpies of Ch3Br and HBr, which is -102.4 kJ/mol + -36.4 kJ/mol = -138.8 kJ/mol.

(b) The overall heat of reaction can be calculated by subtracting the heat of reaction for the second step from the heat of reaction for the first step. The total heat of reaction for the free-radical bromination of metha is calculated as follows: -179.1 kJ/mol - (-138.8 kJ/mol) = -40.3 kJ/mol.ne.

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Chlorine atoms have 7 electrons in the outermost shell. As a result, one would expect chlorine to form ions with a charge of -1.

What is charge of an element?

Due to their equal amounts of protons and electrons, elements typically have no charge. Some atoms can, however, create ions by receiving or losing electrons to acquire a net positive or negative charge. Based on the periodic table group, you may calculate what this charge will be.

Compared to sodium, chlorine attracts electrons more strongly (shown by the thicker arrow). Chlorine is a negative ion with a charge of 1, making it such because it has 1 more electron than protons. Atoms acquire or lose electrons during the formation of ions until their outer energy level is reached.

Therefore, Chlorine has a charge of -1.

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Answer:

23 atoms for the first question

Explanation:

Quick chemical reaction between a material and oxygen that results in the generation of heat and light.

What is combustion?

Combustion is a chemical process that often involves the presence of oxygen and produces heat and light in the form of flames. Because of the nature of the chemical reaction and the fact that more energy is produced than can be released into the surrounding medium, the rate or speed at which the reactants combine is high. As a result, the temperature of the reactants is increased, accelerating the process even more.

A lit match is a common illustration of a combustion process. A flame is produced when a match is struck because friction warms the head to a temperature where the chemicals react and produce more heat than can be released into the atmosphere.

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Permanganate ion that should be added is 0.08 moles. Based on calculation, 0.08 moles of MnO4- ions can oxidize all the iron ions in the flask.

Given:

Therefore:

[tex]\begin{array}{ll}\sf n~MnO_4^- &\sf = \dfrac{coef. ~MnO_4^-}{coef. ~Fe^{2+}}\times n~Fe^{2+}~in\\\\&\sf =\dfrac{1}{5}\times 0.4\\\\&\sf = 0.04~moles.\end{array}[/tex]

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Yes, hydrogen found in a natural abundance, hydrogen is easily the most abundant element in the universe.

Hydrogen the most abundant in nature because hydrogen is the simplest element in the universe, with only one proton and one electron ,it is the only element without a neutron.

The element hydrogen is by far the most abundant in the universe. It can be found in the sun and most stars, and the planet Jupiter is mostly made up of hydrogen. Water is the most abundant form of hydrogen on Earth.

Thus, hydrogen found in a natural abundance.

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Based on this simulation, the following statements are true of strong acids:

- Strong acids have lower pH values than weak acids. This is because strong acids completely dissociate in water, releasing more H+ ions and lowering the pH of the solution.

- Strong acids completely dissociate into H₂O (hydronium) and A (conjugate base) leaving almost no strong acid in the solution. This is a key characteristic of strong acids, as they fully dissociate in water to form hydronium ions and the conjugate base.

- Strong acids dissociate to form more hydronium ions than a weak acid. Since strong acids fully dissociate in water, they release more H+ ions, which combine with water to form more hydronium ions.

The following statements are not true of strong acids:

- When strong acids dissociate, the concentration of the strong acid in the solution becomes negligible. While it is true that strong acids completely dissociate in water, the concentration of the strong acid does not become negligible. The concentration of the strong acid is simply equal to the concentration of the hydronium ions and the conjugate base.

- The products formed when a strong acid dissociates can carry out a reverse reaction to form the strong acid once more. This is not true of strong acids, as they fully dissociate in water and do not undergo a reverse reaction to form the strong acid again.

This is a characteristic of weak acids, which only partially dissociate in water and can undergo a reverse reaction to reform the weak acid.

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Polar molecules dissolve as well as miscible in polar solvents, while nonpolar molecules dissolve and miscible in nonpolar solvents.

Polarity is indeed a division of electric charge in chemistry that results in a molecule and its chemical groups possessing and electric dipole moment with a negative charges end as well as a positive charge end.

Atoms prefer to adopt the configuration of noble gases in order to achieve stability. As a result, we may deduce that chemical bonding was responsible for atom stability and the formation of molecules. Polar molecules dissolve as well as miscible in polar solvents, while nonpolar molecules dissolve and miscible in nonpolar solvents.

Therefore,  polar molecules dissolve as well as miscible in polar solvents, while nonpolar molecules dissolve and miscible in nonpolar solvents.

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The mass balance expression for the sodium is 45.36 mmol and arsenate is 49.98 mmol species in the final solution.

According to the following equation, sodium hydrogen arsenate ([tex]Na_{2} HAsO_{4}[/tex]) and sodium hydroxide ([tex]NaOH[/tex]) react to produce sodium arsenate ([tex]Na_{3} AsO_{4}[/tex]) and water ([tex]H_{2} O[/tex]) when combined:

[tex]Na_{2} HAsO_{4} + 2 NaOH[/tex] → [tex]Na_{3} AsO_{4} + 2 H_{2} O[/tex]

To determine the mass balance expressions for the sodium and arsenate species in the final solution, we need to consider the initial amounts of these species in each of the two solutions and the changes that occur upon mixing.

For the sodium ion ([tex]Na^{+}[/tex]), we have:

Initial amount

= (500.0 mL) x (0.04074 mol/L)

= 20.37 mmol

Amount added

= (500.0 mL) x (0.04997 mol/L)

= 24.99 mmol

Total amount

= 20.37 mmol + 24.99 mmol

= 45.36 mmol

The sodium ion participates in the reaction as a spectator but doesn't change chemically. As a result, the following is the mass balance statement for [tex]Na^{+}[/tex] in the final solution:

[[tex]Na^{+}[/tex]] = 45.36 mmol

For the arsenate ion ([tex]AsO_{4} ^{2-}[/tex]), we have:

Initial amount

= (500.0 mL) x (0.04074 mol/L)

= 20.37 mmol

Amount added

= (500.0 mL) x (0.04997 mol/L) x (2/1)

= 49.98 mmol

Total amount

= 20.37 mmol + 49.98 mmol

= 70.35 mmol

In the reaction, 1 mol of  [tex]Na_{2} HAsO_{4}[/tex]produces 1 mol of [tex]Na_{3} HAsO_{4}[/tex]. Therefore, the amount of [tex]AsO_{4} ^{2-}[/tex]produced is equal to the amount of  [tex]Na_{2} HAsO_{4}[/tex] that reacted. Since we started with 20.37 mmol of [tex]Na_{2} HAsO_{4}[/tex] and it reacts in a 1:1 ratio with [tex]NaOH[/tex], the amount of  [tex]Na_{2} HAsO_{4}[/tex] that reacted is equal to:

Amount of  [tex]Na_{2} HAsO_{4}[/tex] reacted

= (500.0 mL) x (0.04074 mol/L)

= 20.37 mmol

The remaining amount of [tex]AsO_{4} ^{2-}[/tex] in the final solution is therefore:

Amount of [tex]AsO_{4} ^{2-}[/tex] in the final solution

= 70.35 mmol - 20.37 mmol

= 49.98 mmol

The mass balance expression for [tex]AsO_{4} ^{2-}[/tex] in the final solution is:

[ [tex]AsO_{4} ^{2-}[/tex]] = 49.98 mmol

Therefore, the mass balance expressions for the sodium and arsenate species in the final solution are:

[[tex]Na^{+}[/tex]] = 45.36 mmol

[ [tex]AsO_{4} ^{2-}[/tex]] = 49.98 mmol

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There are several mechanisms that can be involved in the synthesis or reactions of alcohols and ethers, depending on the specific reaction and the type of alcohol or ether involved. Here are some common mechanisms that may be involved:

a. Nucleophilic substitution: This mechanism is often involved in the synthesis of ethers from alkyl halides or sulfonates. In this mechanism, a nucleophile attacks the electrophilic carbon of the alkyl halide or sulfonate, displacing the leaving group and forming a new carbon-oxygen bond. In the case of the Williamson ether synthesis, an alkoxide ion acts as the nucleophile and attacks the alkyl halide.

b. Dehydration: In the presence of acid catalysts, alcohols can undergo dehydration to form ethers. This mechanism involves the loss of a water molecule from two alcohol molecules and the formation of an ether linkage.

c. Acid-catalyzed cleavage: Ethers can be cleaved into two alcohol molecules using acid catalysts. This mechanism involves the protonation of the oxygen atom, followed by nucleophilic attack of water or alcohol.

d. Nucleophilic addition: Ethers can undergo nucleophilic addition reactions with strong acids such as HBr or HI to form alkyl halides and alcohols. This mechanism involves the protonation of the oxygen atom, followed by nucleophilic attack of the halide ion.

e. Oxidation: Primary alcohols can be oxidized to form ethers using oxidizing agents such as HIO4. This mechanism involves the oxidation of the alcohol to an aldehyde, which then reacts with another alcohol molecule to form the ether.

f. Acid-catalyzed transetherification: Ethers can react with alcohols in the presence of acid catalysts to form different ethers. This mechanism involves the protonation of one of the oxygen atoms, followed by nucleophilic attack of the alcohol on the other oxygen atom, leading to the formation of a new ether.

g. Acid-catalyzed dehydration of secondary alcohols: Secondary alcohols can undergo acid-catalyzed dehydration to form alkenes and ethers. This mechanism involves the loss of a water molecule from the alcohol, which can lead to the formation of an alkene or an ether depending on the reaction conditions.

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The concentrations of the components will vary as explained below.

(a) If the temperature is increased, the equilibrium will shift in the endothermic direction to consume some of the added heat. This means that the concentration of SO2 and O2 will increase, while the concentration of SO3 will decrease.

(b) If the pressure is increased and the volume is decreased, the equilibrium will shift in the direction that produces fewer moles of gas to relieve the pressure. Since there are 3 moles of gas on the left side of the equation and 2 moles of gas on the right side, the equilibrium will shift to the left to produce more SO2 and O2 and less SO3.

(c) Adding a catalyst will increase the rate of the forward and reverse reactions equally, so the equilibrium concentrations of SO2, O2, and SO3 will remain the same, but they will be reached more quickly.

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According to the forces of attraction , decreasing agitation will decrease the rate of dissolution of a gas in a liquid.

Forces of attraction  is a force by which atoms in a molecule  combine. it is basically an attractive force in nature.  It can act between an ion  and an atom as well.It varies for different  states  of matter that is solids, liquids and gases.

The forces of attraction are maximum in solids as  the molecules present in solid are tightly held while it is minimum in gases  as the molecules are far apart . The forces of attraction in liquids is intermediate of solids and gases.

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Answer:

24.2 cm3 of CO2 will be produced.

Explanation:

This equation is balanced, meaning that the number of atoms of each element is the same on both sides of the equation. To determine the volume of the product, CO2, formed from a reaction of 50 cm3 of CO and 30 cm3 of O2, we need to consider the stoichiometry of the reaction, which states the relative proportions of the reactants and products.

The balanced equation is:

2CO + O2 -> 2CO2

This means that 2 moles of CO react with 1 mole of O2 to produce 2 moles of CO2. To determine the volume of the CO2 produced, we need to know the number of moles of CO and O2.

Assuming that the volumes of CO and O2 are measured at the same temperature and pressure, we can use the ideal gas law to convert the volumes to moles:

n = PV/RT

where n is the number of moles, P is the pressure, V is the volume, R is the gas constant, and T is the temperature.

Let's use 50 cm3 of CO as an example:

n = (1 atm)(50 cm3) / (0.08206 L * atm / mol * K)(298 K) = 0.11 moles of CO

Similarly, we can calculate the number of moles of O2:

n = (1 atm)(30 cm3) / (0.08206 L * atm / mol * K)(298 K) = 0.06 moles of O2

Since the balanced equation states that 2 moles of CO react with 1 mole of O2, we can use the smaller number of moles, 0.06 moles of O2, to calculate the number of moles of CO2 produced:

0.06 moles of O2 * 2 moles of CO2 / 1 mole of O2 = 0.12 moles of CO2

Finally, we can convert the number of moles of CO2 to a volume using the ideal gas law:

V = nRT/P = (0.12 moles)(0.08206 L * atm / mol * K)(298 K) / (1 atm) = 24.2 cm3

So, if 50 cm3 of CO and 30 cm3 of O2 react, 24.2 cm3 of CO2 will be produced.

The arrow pushing mechanisms shows the steps in the reaction.

The question is incomplete but I can see that you want to know something about a reaction that uses an arrow pushing mechanisms to show the steps in the reaction.

Arrow pushing mechanisms are graphical representations used in organic chemistry to show the flow of electrons in a reaction. The arrow symbol is used to represent the movement of electrons from one molecule to another. This makes it easier for chemists to understand and predict the outcome of a reaction by showing the transfer of electrons between reactants and products.

The arrow pushing mechanism provides a step-by-step description of the reaction, starting from the reactants and showing the intermediate stages before reaching the final product. This makes it easier to identify and understand the individual steps involved in a reaction and how they are connected.

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Rank of the given compounds in order of lowest to highest enthalpy of vaporization as follows CH₃NH₂ < CH₃SH < CH₃CH₃.

The enthalpy of vaporization of a substance is related to the strength of its intermolecular forces. Substances with weaker intermolecular forces tend to have lower enthalpies of vaporization, as they require less energy to overcome those forces and vaporize.

In this order, the compounds have increasing strength of intermolecular forces. Methanethiol (CH₃SH) has stronger intermolecular forces than methylamine (CH₃NH₂), and both of these have stronger intermolecular forces than propane (CH₃CH₃).

This is because CH₃NH₂ and CH₃SH can form hydrogen bonds between molecules, while CH₃CH₃ can only experience weaker London dispersion forces.

Hence, the correct option is A.

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The initiation of a tsunami by a stick-slip subduction zone is similar to the motion experienced by reverse  fault.

A reversal fault experiences similar motion as a stick-slip subduction zone when it starts a tsunami. The majority of tsunamis are created by subduction zones, which result in earthquakes when two tectonic plates collide beneath the ocean and encourage the movement of overlapping water.

The energy that builds up as a result of the friction between the plates increases to the point where it may be extrapolated to the limit between the two plates. When a reverse failure occurs in this process, the movement experienced by a reverse failure is analogous to the start of a tsunami through a stick-slip subduction zone.

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On Earth he weighs 720 newtons. 36N is the weight. Therefore, the correct option is option D among all the given options.

The gravitational force of attraction exerted on an item by the presence of a huge second object, including the Earth or Moon. Weight is a result of the fundamental law of gravitation: whatever two things have the same weight.

They attract each other using a force that really is directly related to the sum of their masses as well as inversely related to the square of something like the distance separating them due to their masses.

F = mass ×4/9g

  = 720 ×4/9

  =36N

Therefore, the correct option is option D.

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Number of moles = 0.0250839 mol (rounded to 7 significant figures) of compound X in 25.1085 g, we need to divide the given mass by the molar mass of X.

Using the given molar mass, we have calculated the number of moles of X in 25.1085 g to be 0.0250839 mol. We should round this value to the appropriate number of significant figures based on the given data. Since the mass is given to 7 significant figures.

Molar mass is the mass of one mole of a substance, usually expressed in units of grams per mole (g/mol). It is calculated by adding up the atomic masses of all the atoms in a molecule.

The molar mass of an element is equal to its atomic mass in grams per mole. For example, the molar mass of carbon is 12.01 g/mol, which is the atomic mass of carbon rounded to two decimal places.

Number of moles = Mass ÷ Molar mass

Number of moles = 25.1085 g ÷ 1000.7 g/mol

Number of moles = 0.0250839 mol

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-Expand the volume of the gas while keeping moles of gas and temperature constant.

-Decrease the temperature of the gas while keeping volume and moles of gas constant.

When the volume of a gas increases, the pressure decreases, as long as the temperature remains constant. This is known as Boyle's law. Therefore, one way to decrease gas pressure is to increase the volume of the container that holds the gas.

As the temperature of a gas decreases, its pressure also decreases, as long as the volume remains constant. This is known as Charles's law. Therefore, one way to decrease gas pressure is to cool the gas down.

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The total strain energy can be estimated by adding up the contributions from each type of strain. For the eclipsed conformation of 2,3-dimethylbutane, the total strain energy is approximately 3.8 kcal/mol.

To draw a Newman projection of 2,3-dimethylbutane along the C2-C3 bond, we need to imagine looking along that bond and represent the carbon atom that is closer to us as a point (•) and the carbon atom that is farther away as a circle (o). We then draw the substituents on each carbon as follows:

To calculate the total strain energy of this conformation, we need to consider the various types of strain that are present.

The main sources of strain in this conformation are:

Torsional strain: The eclipsed conformation of the C2-C3 bond creates torsional strain.

The dihedral angle between the two methyl groups is 0°, which means they are eclipsed and experience torsional strain.

Steric strain: The two methyl groups are close to each other and experience some degree of steric strain.

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The unit for the rate constant of a second order reaction is [tex]L mol ^{-1} s^{-1}[/tex] . Option d is the correct answer.

Second order reactions can be defined as chemical reactions wherein the sum of the exponents in the corresponding rate law of the chemical reaction is equal to two. The rate of such a reaction can be written either as r = k[A]2, or as r = k[A][B].

The unit for the rate constant of a second order reaction is [tex]L mol ^{-1} s^{-1}[/tex] .

For a second order reaction, rate=k[A]^2.

[tex]mol L^{-1} s^{-1} = k (molL^{-1})^2[/tex]

k = [tex]L mol ^{-1} s^{-1}[/tex] .

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--The complete question is, What is the unit for the rate constant of a second order reaction?

a. s^-1

b. molL^-1

c. molL^-1s^-1

d. Lmol^-1s^-1

e. mol^2L^-2s^-2--

The reactant in a chemical process that releases less energy than the result does the following. Heat absorption will help the reaction move forward.

Heat absorption refers to the process by which a material or object takes in and retains thermal energy from its surroundings. This can occur through several mechanisms, including conduction, convection, and radiation.

The ability of a material to absorb heat is determined by its specific heat capacity, which is a measure of how much energy is required to raise the temperature of the material by a given amount. Materials with a high specific heat capacity can absorb more heat without experiencing a significant increase in temperature.

Heat absorption has important implications in many areas of science and engineering, including thermodynamics, materials science, and climate science. It is also relevant to everyday life, as it affects the performance of various devices and systems, such as air conditioning units, solar panels, and cooking appliances.

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The complete question is:

Which of the following is true about a chemical reaction in which the reactant stores less energy than the product?

Among the following compounds, a strong electrolyte is NaF. It gives its constituent ions Na+ and F- when dissolved in water.

Electrolytes are molten or liquid substances containing ions which are free to move within the solution. There are two types of electrolytes namely strong electrolytes and weak electrolytes.

Strong electrolytes are those which are able to completely dissociates into its ions and thus conduct current. Weak electrolytes are weakly ionize or do not dissociates into its ions completely.

NaOH, KOH, NaCl , NaF etc are strong electrolytes. Whereas acetic acid, HF, water etc. are weak electrolytes. Strong ionic compounds are strong electrolytes too. Hence, NaF is the correct option.

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The mode is the value that appears most frequently in the data set. In this case, the value of 5 appears most frequently, occurring 4 times. Therefore, the mode of the number of boxes of graduated cylinders that were ordered for each lab of a college science department is 5.

The mode is a statistical measure that represents the value that appears most frequently in a data set. It is a useful measure of central tendency, especially when dealing with nominal or categorical data. The mode can be easily found by identifying the value with the highest frequency in the data set. In some cases, a data set may have multiple modes if there are two or more values with the same highest frequency.

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Answer: All visible light waves except red are absorbed by the ball. The wave transfers its energy to the material.

Explanation: The red is reflected back, which is how we see color. This is why most plants look green, they cannot absorb green light.

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The main purpose of the paragraph is to D. To provide information about the author Ernest Cline

The goal or objective of a writer is their motivation for writing. An author may want to parody a condition, persuade the reader, inform the reader, or amuse the reader.

The primary motivation for an author's writing is that author's purpose. The three main goals are to entertain, convince, and inform. You can determine an author's purpose by using the straightforward technique shown below.

In this case, information was provided about the character.

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What is the main purpose of this

paragraph?

A. To teach a moral though metaphor

B. To persuade by sharing a perspective about a subject

C. To entertain the audience

D. To provide information about the author Ernest Cline

Isopropyl alcohol (C3H8O) is a polar molecule due to the presence of an OH group. The types of intermolecular forces that would occur between the solute (isopropyl alcohol) and the solvent depend on the nature of the solvent. In general, polar solutes dissolve in polar solvents, and the intermolecular forces that occur are:

Hydrogen bonding: Isopropyl alcohol can form hydrogen bonds with other polar molecules, including water or other alcohols. Hydrogen bonds occur between the hydrogen atom of the OH group in isopropyl alcohol and the lone pair of electrons on the oxygen atom of the other molecule.

Dipole-dipole interactions: Isopropyl alcohol can also experience dipole-dipole interactions with other polar molecules. Dipole-dipole interactions occur when the positive end of one polar molecule is attracted to the negative end of another polar molecule due to their partial charges.

In summary, the intermolecular forces that would occur between isopropyl alcohol and a polar solvent, such as water or another alcohol, are hydrogen bonding and dipole-dipole interactions.

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(i) Cyclohexane acts as a good solvent at a temperature of T = 80 °C because it is above the θ-temperature of 34.5 °C.(ii) The value of T above which the system is athermal is the θ-temperature, which is 34.5 °C for polystyrene in cyclohexane.

i) In a good solvent, the polymer coils expand and the polymer-solvent interactions are stronger than the polymer-polymer interactions.

Therefore, Cyclohexane acts as a good solvent at a temperature of T = 80 °C because it is above the θ-temperature of 34.5 °C.

This can be mathematically justified by the Flory-Huggins equation: χ = (V1/RT)(ΔH - TΔS)

where χ is the Flory-Huggins interaction parameter, V1 is the molar volume of the solvent, R is the gas constant, T is the temperature, ΔH is the enthalpy of mixing, and ΔS is the entropy of mixing.

At temperatures above the θ-temperature, χ is negative, indicating that the polymer-solvent interactions are stronger than the polymer-polymer interactions and the solvent is a good solvent.

(ii) The value of T above which the system is athermal is the θ-temperature, which is 34.5 °C for polystyrene in cyclohexane.

Above this temperature, the polymer-solvent interactions are stronger than the polymer-polymer interactions and the solvent is a good solvent.

The boiling point of cyclohexane is 80.7 °C, so this temperature is accessible under standard conditions (P=1 atm).

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The feet is a standard unit of measurement. It is mainly used to measure the length of a particular object. Here 12 mi is 63,360 feet. The correct option is B.

The unit of measurement which is generally used to measure height, length and distance is defined as the feet. The foot is the singular form of feet. It is a non-metric measure unlike meters and centimeters which are metric.

Here 1 mi = 5280 ft

Then,

12 mi = 12 ×  5280

= 63,360 feet

Thus the correct option is B.

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