Calculate the cfse for a d^3 system in an octahedral field in units of ∆_o. In other words, do not enter "∆_o" with your answer. For example, if your answer is −0. 8∆_o, then enter "−0. 8. ".

Simple cubic structure there is only one lattice point at each corner of the cube-shaped unit cell. Here, particles are present at the corners of the cube and not on the body center or face center.

Alpha polonium is a high radioactive heavy metal.

How to calculate density in simple cubic cell?

We will use the equation,

ρ=Z×Ma/a³×Na

where,

Z = number of atoms in a unit cell (Z = 1 for a simple cubic unit cell)

a = edge length= 336 pm

Na=6.022×1023particles/mol

Ma = 209

ρ=Z×Ma/a³×Na

= 1× 209 / (336) ³× 6.023

= 3.31 ^-5

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The main function of the coarse adjustment knob simply is that it helps to focus an image on the microscope.

In science, a microscope is an instrument which is used in viewing objects or cells which cannot be be seen with the ordinary eyes. This instrument is also used to view microscopic organisms, cell and tissues.

That being said, the coarse adjustment knob help in focusing an image on the microscope by way of moving the stage up and down and the lens too. Some few parts of microscope aside the coarse adjustment knob are as follows:

In conclusion, it can be deduced from all said and done above that objectives lens and the stage of the microscope helps the coarse adjustment knob to perform its function easily.

Complete question:

Description/Functions Illuminating/magnifying/mechanical parts of microscope.

What is the function of the coarse adjustment knob of a microscope?

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Helium atoms do not combine to form he2 molecules, yet he atoms do attract one another weakly through dispersion forces.

The weakest intermolecular force is called the dispersion force. When the electrons in two nearby atoms occupy positions that cause the atoms to temporarily form dipoles, the resulting temporary attractive force is known as the London dispersion force. An induced dipole-induced dipole attraction is another name for this force. The attractive forces known as London forces are what cause nonpolar substances to condense into liquids and to freeze into solids when the temperature is sufficiently lowered.

An atom or molecule can produce an instantaneous (temporary) dipole when its electrons are dispersed asymmetrically around the nucleus due to the electrons' constant motion.

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The original concentration in the sample is 4.3 × [tex]10^{4}[/tex] CFU/mL.

What is colony forming unit?

Colony forming units, or CFUs, are frequently used to calculate the number of microorganisms present in a test sample. A CFU/ml result can be obtained by multiplying the number of visible colonies (CFU) present on an agar plate by the dilution factor.

Given:

CFU in 1.0mL of [tex]10^{-3}[/tex] dilution is 43.

Total CFU in original sample = [tex]\frac{Plate count}{Dilution factor}[/tex]

= [tex]\frac{43}{10^{-3} }[/tex] = 43000

S0,  1 mL of the original sample = 4.3 × [tex]10^{4}[/tex] CFU.

we know, cell density of the sample  = no. of cells per mL of solution.

= 4.3 × [tex]10^{4}[/tex] CFU/mL.

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The wavelength of radiation of resonance absorption is 3.55 x 10⁻⁷ nm. If the first excited state of an atom of a gas is 1.85ev above the ground state.

First, we need to Calculate the frequency of the radiation.

Since the energy of the first excited state is 1.85 eV, we can calculate the frequency of the radiation (ν) using the equation

ν = E/h,

where E is the energy in Joules and h is the Planck's constant (6.626 x 10⁻³⁴ Js).

Therefore,          

ν = 1.85 x 1.60 x 10⁻¹⁹J/ (6.626 x 10⁻³⁴ Js)

ν = 2.81 x 10¹⁵ Hz

Next we need to Calculate the wavelength of the radiation.

The wavelength of radiation (λ) is the inverse of the frequency (ν), so

λ = 1/ν.

Therefore,

λ = 1/ (2.81 x 10¹⁵ Hz)

λ = 3.55 x 10⁻¹⁶ m

Lastly, Convert the wavelength from meters to nanometers.

1 m = 10⁹ nm

Therefore, 3.55 x 10^-16 m = 3.55 x 10⁻⁷ nm

The wavelength of radiation for resonance absorption is 3.55 x 10⁻⁷ nm

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a) the pressure in the container will increase when a sample of gas is heated steadily in a closed rigid container.

Both the kinetic energy and the gas pressure will rise as a result. Typically, a rise in temperature will result in a rise in volume. The volume of the container cannot rise since the gas is contained inside a rigid container.

By definition, an increase in temperature results in an increase in kinetic energy. The gas's molecules will travel more quickly as a result of the increase in kinetic energy. The molecules smash more forcefully with one another as they move more quickly. Pressure will rise as a result of these encounters.

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The total time is =405,189.19 h.

What is time?

Time is the indefinite continued progress of existence and events that occur in an apparently irreversible succession from the past, through the present, to the future. It is the measure in which events can be sequenced, and compared to the events of the past and future. Time is a fundamental quantity that is used to sequence events and to compare the durations of events and the intervals between them. Time is usually divided into units such as seconds, minutes, hours, days, weeks, months and years, and can be further divided into smaller increments such as milliseconds, microseconds and nanoseconds.

The reaction is
2H+(aq)+2e−→H2(g)
To produce 1 mole of hydrogen, 2 moles of electrons are necessary
So to produce 1 mole of hydrogen, 96000×2C are needed.
Number of moles hydrogen =9.37mol
Quantitity of electricity is
Q=9.37⋅2⋅96000C=1799040C
The current is I=74⋅10−3A
Q=It
The time is
t=Q/I=1799040⋅0 /74 x 10−3s = 24,311,351.4 s= 405,189.19 h

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The elements F and N are gases at room temperature. Both exists as diatomic gases (N2, F2), the compounds, only CO2 and N2O are gases, others are solid at room temperature.

What is gas?

A sample of matter that develops a uniform density inside a container and conforms to the shape of the container it is held in, despite gravity and regardless of the volume of the container in which it is held.

What is  room temperature?

A temperature range that is comfortable for residence by humans is referred to as "room temperature." A person wearing typical attire experiences neither heat nor cold in this temperature range. When utilizing absolute temperature, it is also possible to use 300 K, or 27 o C, as the standard room temperature in science.

The elements F and N are gases at room temperature. Both exists as diatomic gases (N2, F2).

He, Xe and Kr are noble gases, they are monatomic and are gases in room temperature.

Among the compounds, only CO2 and N2O are gases, others are solid at room temperature.

Therefore, the elements F and N are gases at room temperature. Both exists as diatomic gases (N2, F2), the compounds, only CO2 and N2O are gases, others are solid at room temperature.

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The effects on carbonyl bond strength of adding one, and then two. oxygens: Both carboxylic acids and esters contain a carbonyl group with a second oxygen atom bonded to the carbon atom in the carbonyl group by a single bond.

The Nucleophile (Nu) attacks the positively charged carbon and pushes one of the double-bond electrons onto oxygen to give it a negative charge.

In organic chemistry, a carbonyl bond is a functional institution composed of a carbon atom double-bonded to an oxygen atom: C=O. it's far commonplace to several instructions of natural compounds, as part of many larger functional groups. A compound containing a carbonyl institution is often called a carbonyl compound.

A carbonyl organization consists of a double bond linking a carbonyl carbon atom and a carbonyl oxygen atom. The carbonyl oxygen atom shares its six valence electrons with the carbonyl carbon atom. Its last 4 valence electrons remain as two sets of electron lone pairs.

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1.5 moles of Octane will react to produce = (1.5 × 18)/2 = 13.5 moles of H2O.

Thus, 13.5 moles of water were obtained from the reaction.

We'll begin by writing the balanced equation for the reaction. This is illustrated below below:

2C8H18 + 25O2 —> 16CO2 + 18H2O

From the balanced equation above,

2 moles C8H18 reacted to produce 18 moles of H2O.

Finally, we shall determine the number of moles of H2O produced by the reaction of 1.5 moles of C8H18. This can be obtained as follow:

From the balanced equation above,

2 moles C8H18 reacted to produce 18 moles of H2O.

Therefore, 1.5 moles of C8H18 will react to produce = (1.5 × 18)/2 = 13.5 moles of H2O.

Thus, 13.5 moles of H2O were obtained from the reaction.

If that happens, we know from the balanced equation that for every two moles of octane consumed, we get 18 moles of H2O.

The law of conservation of mass, which states that "the total mass of all the products of reaction in a chemical reaction is equal to the total mass of all the reactants," is satisfied by balancing chemical equations.

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SF₆ is the gas, that is most likely to depart from the assumption of the kinetic-molecular theory that says there are no attractive or repulsive forces between molecules.

What is Kinetic- molecular theory?

The assumption that matter is made up of microscopic particles that are always in motion forms the foundation of the kinetic-molecular theory, which explains the states of matter. The observable characteristics and behaviours of solids, liquids, and gases are explained by this theory.  The theory specifically pertains to the ideal gas model of a gas. An ideal gas is a hypothetical gas whose behaviour exactly matches all of the kinetic-molecular theory's presumptions.

What are molecules?

The smallest component of a substance possesses both its chemical and physical characteristics. One or more atoms make up molecules. They may have the same atoms or different atoms if they have more than one (a water molecule has two hydrogen atoms and one oxygen atom).

Hence, SF₆ is the gas, that is most likely to depart from the assumption of the kinetic-molecular theory.

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The molarity of the NaOH is 0.25M.

What is molarity?

The molar concentration or the molarity of the solution is inversely proportional to the dilution. An increased dilution will decrease the molarity of the solution.

What is concentration?

How much solute has been dissolved in the solvent is indicated by the concentration of the solution.

Therefore,  molarity of the NaOH is 0.25M.

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The chemist prepares a solution of calcium sulfate by measuring out 0.53 umol of calcium sulfate into a 350 ml volumetric flask and filling the flask to the mark with water. The concentration of a solution is 1.5 uM.

The concentration or molarity of a solution is defined as the number of moles present in the specific volume of a solution. It is calculated as

Concentration=moles/volume(in L)

The volume of a solution is in mL. Convert the given volume in L

350 ml×(1 L/1000 mL)=0.35 L

Plug the value of moles and volume in the formula

Concentration=0.53 umol/0.35 L

Concentration=1.51429 umol/L

Concentration=1.5 uM (∵M=mol/L)

Therefore, the concentration of a solution is 1.5 uM.

I have answered the question in general as given question is incomplete. The complete question is

a chemist prepares a solution of calcium sulfate by measuring out 0.53 umol of calcium sulfate into a 350 ml volumetric flask and filling the flask to the mark with water. calculate the concentration in uM of the chemist's calcium sulfate solution. round your answer to two significant digits.

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The methyl group is toluene is not on meta position. The methyl group is electron releasing group.

In case of toluene, the methyl group connected to the ring, will increase the electron density at ortho and para positions via way of means of resonance with out converting some thing on the meta position. Thus the attacking reagent at once assaults on the electron wealthy site , accordingly the methyl institution is ortho directing. you may effortlessly apprehend the motion of electrons via way of means of following the route of arrows in structures. There isn't any shape wherein the electrons may be visible on meta position.

The resonating structures of toluene is attached below.

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The total mass of BF3 present is 5.552 g

What do you mean by ideal gas equation?

The Ideal gas law is the equation of state of a hypothetical ideal gas. It is a good approximation to the behaviour of many gases under many conditions, although it has several limitations. The ideal gas equation can be written as.

PV = nRT

Where,

P is the pressure of the ideal gas.

V is the volume of the ideal gas.

n is the amount of ideal gas measured in terms of moles.

R is the universal gas constant.

T is the temperature.

Given situation is ,

( P) Pressure of BF3 gas is 1.220 atm

( V) Volume of BF3 is 4.3410L

( T) Temperature of BF3 is 788.0 K

Now, assuming this as an ideal gas,

Let us apply ideal gas equation,

PV = nRT

n = PV/RT = 1.220 atm * 4.3410L / 0.0821 L atm k-1 mol-1 * 788 K

n = 0.08186 moles of BF3 are present.

Now, we know molar mass of BF3 = 67.82 gmol-1

i.e. total mass of BF3 present = Number of moles * molar mass

                                                = 0.08186 * 67.82g mol-1

                                                = 5.552 g of BF3 is present.

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After dragging the chlorine atom from number one carbon atom to the second one, it would be 2-cloromethyl-4-cylcopentane.

As chloride ions are larger in size than fluoride ions, oxide ions and most of cations of the metallic elements, it is difficult for them to migrate easily in solids. However, some chloride ion conductors are known although their conductivity is low compared to that of fluoride ion conductors.

     SnCl2 shows higher chloride ion conductivity than a PbCl2-based conductor, but it is chemically unstable in the atmosphere.

   As per the given condition we have to replace the chlorine from number one atom to the second atom in order to get the resonance structure.

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The kinetics of first order governs nuclear decay. A rate constant for a nuclide, which decays from 12.9 g to 2.04 g in 23.0 minutes, is 0.08.

identifying the root of the problem. The essential elements of a family, commonly their parents and kids, are referred to as the "nuclear family" in this phrase. Nuclear has a long history of metaphorical usage prior to its main association to "nuclear energy," with its meanings including "core" and even more merely "something basic."

As far as we are aware, the first order reaction rate is provided by:

               kt=2.303*log(R'/R)

We are aware that the following equation determines the rate of a first order reaction:

where k = rate of reaction

          t = time = 23 minutes

         R = end mass = 2.04 grams,

         where R' = beginning mass = 12.9 grams.

We obtain k = 0.08 by plugging these values into the equation above.

i.e., the nuclide's rate constant is 0.08.

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The Percent yield is  65.7%.

As per the reaction:

2H2(g)+O2(g)→2H2O(g)

This translates to two moles of hydrogen generating two moles of water, resulting in an excess of oxygen.

What is percent yeild?

The percentage yield indicates how much product is produced in relation to the maximum mass that may be produced. A reaction's atom economy indicates the proportion of atoms in the reactants that go into producing the intended result.

To determine the percent yield, we must first determine the theoretical yield. We can calculate percent yield as 100 times the difference between actual yield and theoretical yield using both theoretical and percent yield (32.8g H2O).

Theoretical yiled:

5.58g H₂ₓ (1 mol/2.016g) = 2.768 moes H₂

As 2 moles of H₂ produce 2 moles of H₂O, if all hydrogen react will produce 2.768 moles H₂O.

In grams: 2.768 moles H₂O×(18.015g/mol) = 49.86g H₂O

Hence, theoretical yield = 49.86g H₂O

Percent yield:

Percent yield = Actual yield/Theretical yieldₓ100

                      = 32.8g H₂O/49.86g × 100

                      = 65.7%

Therefore, Percent yield is  65.7%.

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Fractional bond orders are frequently produced by partial bonding, such as when it's a component of a resonance hybrid.

Resonance hybrid: what is it?

Resonance structures are collections of two or more Lewis structures, including fractional bonds and fractional charges, that collectively represent the electronic bonding of a single polyatomic species.

Resonance structures can represent delocalized electrons that are not described by a single Lewis formula with an integral number of covalent bonds.

Do resonance hybrids include any partial charges?

A resonance structure must never have any net formal charge. On the other hand, the weighted average of the formal plus partial charges on an atom in each resonance contributor is the net partial charge on that atom.

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Our mole ratio is 94: 4.0: 1.5: 0.50.

This suggests that there are 94 + 4.0 + 1.5 + 0.50 = 100 moles of natural gas in total.

Consider the formula: partial pressure = mole fraction * total pressure.

In the case of CH4, 94/100 * 1.48 atm = 1.39 atm

C2H6: 4/100 * 1.48 atm = 0.0592 atm

C3H8: 1.5/100 * 1.48 atm = 0.0222 atm

For C4H10, multiply 0.5/100 by 1.48 atm to get 0.0074 atm.

the proportion between the moles with one component in a fluid or other combination and the total moles of all the components.

By dividing the total amount of moles of all the elements in a solution by the number of moles within one component in a solution, the molar ratio can be computed. It should be noted that the mole fractions of each component in the solution added up should equal one.

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I understand the question you are looking for is :

Natural gas is a mixture of many substances, primarily CH4, C2H6, C3H8, and C4H10. Assuming that the total pressure of the gases is 1.48 atm and that their mole ratio is 94 : 4.0 : 1.5 : 0.50, calculate the partial pressure in atmospheres of each gas.

Learn the concentration and beginning rate in order to determine the correct number of significant digits. The starting rate of reaction is 98.0 m/s at a specific concentration of h2 and i2.

What, using an example, is concentration?

1) Percent Concentration:

The amount of solute that completely dissolves in 100 g of solvent. We know that there are 20 g of solute in 100 g of solution if the solution's concentration is 20 percent. Example: The solution is made by combining 10 g of salt with 70 g of water. Find the solution's concentration using mass percent.

What would you say about concentration?

The amount of solute contained in a specific amount of solution is the substance's concentration. Typically, concentrations are described in terms of molarity, which is the number of

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The neutralization reaction between the weak acid H2S(aq)and the strong base KOH(aq) can be represented using the following total ionic equation.

2H2S+K^+ + 20H^- → 2H2O +2S^2- + K^+

From this equation, we can see that the spectator ion would be the K+ion since it is present in both sides.

Spectator ions exist on both sides of the equation in the same state because they are present during the reaction but are unaffected by it. Every neutralization reaction involves this shift.

Ions present in a reaction solution but not participating in the reaction are known as "spectator ions." As ions, they persist in solution. In this instance, both the hydride H+ and hydroxide OH1 ions from the LiOH and HBr remain in solution.

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The ag | agcl and calomel reference electrodes are saturated with kcl. The answers should be as follows : (a) 0.326 v, (b) 0.086 v, (c) 0.019 v, (d) -0.021 v, (e) 0.021 v.

Chemical reaction known as oxidation. As a result of atoms as well as groups of atoms losing electrons, it is described as a process. The addition or loss of oxygen as well as hydrogen in such a chemical species would be another method to describe oxidation.

(a) 0.523 v versus S.H.E. = ? versus Ag | AgCl

E(measured) = E(ind) - E(red)

                     = 0.523 - 0.197

                     = 0.326 v

(b) - 0.111 v versus Ag | AgCl = ? versus S.H.E.

E(measured) = E(ind) - E(red)

0.197 = E(ind) - (-0.111)

E(ind) = 0.197 - 0.111

E(ind) = 0.086 v

(c) -0.222 v versus S.C.E. = ? versus S.H.E.

E(measured) = E(ind) - E(red)

0.241 = E(ind) - (-0.222)

E(ind) = 0.241 - 0.222

E(ind) = 0.0019 v

d) 0.023 v versus Ag | AgCl = ? versus S.C.E.

E(red) = 0.241 - 0.197 = 0.044

E(measured) = E(ind) - E(red)

                     = 0.023 - 0.044

                     = -0.021 v

(e) - 0.023 v versus S.C.E. = ? versus Ag | AgCl

E(measured) = E(ind) - E(red)

0.044 = E(ind) - (-0.023)

E(ind) = 0.044 - 0.023

E(ind) = 0.021 v

Hence, The responses are (a) 0.326 v, (b) 0.086 v, (c) 0.019 v, (d) -0.021 v, and (e) 0.021 v.

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5.26 years later, that 50 grams of cobalt remain is the correct prediction that chemist can predict exactly which cobalt atom is going to decay.

A chemical element with the atomic number 27 and the symbol Co is cobalt. With the exception of minor concentrations found in alloys of naturally occurring meteoric iron, cobalt is only ever found in the Earth's crust in a chemically mixed state. Because of its look, hardness, and resistance to oxidation, cobalt is frequently used in electroplating.

Destructive dissolution is what is meant by the words decay, decompose, rot, putrefy, and spoil. The term "decay" refers to a gradual deterioration from a sound or perfect state. a dilapidated home. Decomposition causes a breakdown by chemical transformation and corruption when applied to organic substance. Because objects that are rotting or decaying typically don't look good or smell good, decay seems like an unpleasant process.

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C. Food Irradiation

Explanation:

The combined masses of the acid and base, the enthalpy change would be less than anticipated.

What is pH?

An aqueous solution's pH indicates how basic or acidic it is; a pH of 7 or less indicates that the solution is basic. 7 is regarded as the neutral pH. The pH scale typically ranges from 0 to 14, though extremely strong acids and bases may have pH values that are higher than 14.

As 50 ml of HCl are needed to make 50 ml of NaOH, but Jacob only added 40 ml, all the H+ ions are consumed, and this limiting reactant is what prevents the production of the desired product.

[tex]NaOH + HCl - > NaCl + H2O[/tex]

Instead of NaOH, HCl would act as the limiting reactant. This error would result in fewer product. Due to the volume shift, this would also have an impact on the pH levels of the solution. Additionally, by reducing the combined masses of the acid and base, the enthalpy change would be less than anticipated.

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the ag | agcl and calomel reference electrodes are saturated with kcl.

a) +0.326 V vs Ag/AgCl for 0.523 V vs Ag/AgCl

    +0.523- 0.197= 0.326

e) 0.021 V vs Ag/AgCl

+0.218-0.197= 0.0021

Calomel  reference electrode is a salt electrode that is readily soluble in metals. It serves as a supplemental reference electrode to ascertain the electrode's standard potentials. Construction: The electrode is made of a glass tube with a bent side tube and another side tube, designated B.

Using a platinum wire contained in a glass tube and submerged in a layer of mercury, an external electrical contact is created. A salt bridge and the side tube come into touch electrically. The calomel electrode can act as either an anode or a cathode depending on the makeup of the other electrodes in the cell.

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Entropy generation cannot be negative, but entropy change can be for a system or its surroundings.

The total entropy is negative if the amount of heat released exceeds the amount of heat absorbed. As a result, total entropy can be negative, and a reaction loses its spontaneity in this case.

When the entropy changes negatively, it means that an isolated system's disorder has diminished. Because liquid particles are more disordered than solid particles, the reaction that turns liquid water into ice, for instance, represents an isolated decrease in entropy.

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The mass of manganese required is 0.918 g.

What is chemical equation?
Chemical equations are symbols but also chemical formulas that represent a chemical reaction symbolically. With a plus sign separating the entities in the reactants and the products and an arrow pointing in the direction of the products to indicate the direction of the reaction, the reactant entities have been given on the left as well as the product entities on the right. Chemical formulas can be mixed, structural (represented by pictures), or both. The absolute values of a stoichiometric numbers are shown as coefficients alongside the symbols and formulas of the various entities. Jean Beguin drew the first chemical equation in 1615.

Start with a balanced equation.
MnO₂(s) + 4HCl(aq) --> 2H₂O(l) + Cl₂(g) + MnCl₂(aq)
Calculate the moles of Cl₂ in 385 mL under the conditions given, using the ideal gas law.

PV = nRT

Known and Unknown
P = 785 Torr
V = 250 mL × 1 L/1000 mL = 0.250 L
n = ? mol
R = 62.364 L•Torr/K•mol
T = 25 °C + 273 = 298 K

Solve for n.
n = PV/RT
n = (785 Torr × 0.250 L)/(62.364 L•Torr/K•mol × 298 K) = 0.01056 mol Cl₂
Calculate the moles of MnO₂ required to produce 0.01056 mol Cl₂ in excess HCl, using the mole ratio between MnO₂ and Cl₂.
Since the mole ratio between MnO₂ and Cl₂ is 1:1, 0.01056 mol Cl₂ is produced by 0.01056 mol MnO₂.
Calculate the mass of MnO₂ in 0.01056 mol.
mass (m) = moles (n)/molar mass (M)
M(MnO₂) = 54.938 g/mol Mn + (2 × 15.999 g/mol O) = 86.936 g/mol MnO₂
m(MnO₂) = 0.01056 mol × 86.936 g/mol = 0.918 g Cl₂
The mass of manganese required to react with excess HCl to produce 0.01056 mol Cl₂ is 0.918 g.

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The volume of 5.1 m H₂O₂ stock solution that should be used to prepare the solution is 9.80 ml.

Dilution is defined as the process in which the concentration of a sample is decreased by adding more solvent. The dilution formula is given below.

C₁V₁ = C₂V₂

where C₁ = initial concentration of sample = 5.1 m

V₁ = initial volume of sample

C₂ = final concentration after dilution = 1.00 m

V₂ = total final volume after dilution = 50.0 ml

Plug in the values to the formula and solve for the volume of the solution needed.

V₁ = C₂V₂/C₁

V₁ = (1.00 m)(50.0 ml)/(5.1 m)

V₁ = 9.80ml

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