Calculate the mass in 488 mol of calcium carbonate, CaCO3

The volume of the unit cell of element X is approximately 1.785 × 10⁸ picometers cubed (pm³).

In a body-centered cubic unit cell, there are atoms at each of the eight corners of the cube, and one atom in the center of the cube. Each atom at the corner is shared by eight unit cells, while the atom at the center is contained within a single unit cell.

The distance from one corner of the cube to the opposite corner is equal to four times the radius of the atom (i.e. 4 × 151 pm = 604 pm), which is known as the body diagonal of the cube.

Therefore, the length of one side of the cube is given by:

a = (4/√3) × r

= (4/√3) × 151 pm

≈ 554.6 pm

The volume of the unit cell is then given by:

V = a³

= (554.6 pm)³

≈ 1.785 × 10⁸ pm³

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1.852 grams of H₂ are produced when 67.12 grams of HCl are reacted with copper.

A mole is a important unit of measurement. 1 mole =  6.023 × 10²³ particles.

The term mole is defined as the amount of matter containing 6.023 × 10²³ molecules.

For each two moles of HCl there is one mole of hydrogen.

So first convert the grams to moles.

Then find formula mass of HCl

The mass of hydrogen = 1.007 amu

mass of chlorine = 35.453 amu

Then 1.007 + 35.453 = 36.46 grams

Hence, one mole of HCl = 36.46 grams/mol

67.12g ÷ 36.46 = 1.84 moles

Therefore, 1.84 mols / 2

= 0.92 moles of hydrogen

Now to convert the moles into grams by multiply the number of moles of hydrogen by the atomic mass of hydrogen

= 0.92 mols × 2.014 g/mol

= 1.852 grams of hydrogen

We get 1.852 grams of hydrogen.

Thus, 1.852 grams of H₂ are formed.

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The oxidation state of an ion is the same as the number of electrons accepted or given away by the atom (option C).

Oxidation state is the total number of electrons that an atom either gains or loses in order to form a chemical bond with another atom.

Oxidation state is also referred to as oxidation number, and it is the state of an atom having a particular oxidation number.

Examples of oxidation number are as follows:

Therefore, option C is synonymous to the oxidation state of an ion.

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From the table of plots of solubility, it is clear that, the solubility of ammonia in 100 g of water is 55 g at 20°C. Then, the solubility at the same temperature for 200 g of water is 110 g.

Solubility of a substance in a solvent at a specified temperature is the fraction of its concentration that can be dissolved in  the solvent. Solubility depends on the bond type of the substance, its molecular mass, temperature and pressure.

For most of the salts, as the temperature increases, solubility increases. But for some compounds solubility decreases with temperature. From the graph, it is clear, that, the solubility of ammonia decreases with temperature.

The solubility of ammonia at 20 °C in 100 g of water is 55 g. Then, at this temperature, the solubility of ammonia in 200 g of water will be 110 g. Then, to form a saturated solution, 110 g or above of ammonia can be added.

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Table G of your question is attached below:

The statement that, the particles are so small compared with the distances between them that the volume of the individual particles can be assumed to be zero is true.

This statement is a reasonable approximation for the behavior of particles in a gas or a dilute solution, where the individual particles are separated by relatively large distances. In these cases, the particles are typically much smaller than the average distance between them, so their volume can be assumed to be negligible.

However, in condensed phases such as liquids and solids, the particles are much closer together, and their volumes cannot be ignored.

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4 m is the wavelength of Wave B.

What is wavelength?

The Greek letter lambda (λ), which represents wavelength, is frequently used. When describing modulated waves, their sinusoidal envelopes, or waves created by the interference of several sinusoids, the term wavelength is also occasionally used.

What is frequency ?

The number of full wave cycles that pass a spot in a unit of time is described as frequency. The frequency in SI is measured in Hertz (Hz).

Therefore, 4 m is the wavelength of Wave B.

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Answer: Phosphorus

Explanation:

Amphipathic molecules contains both hydrophilic and hydrophobic portions.

Amphipathic molecules are defined as those molecules that are both hydrophilic as well as hydrophobic in nature. For example, phospholipid is an amphipathic molecule which have a hydrophilic head while its acyl tail being hydrophobic.

All of the lipid molecules present in the cell membranes are amphipathic in nature—that is, they have a hydrophilic (“water-loving”) or polar end and a hydrophobic (“water-fearing”) or nonpolar end.

The carbohydrate that forms the hydrophilic head, and the fatty acids form the hydrophobic tail. Phospholipids in structure, generally these lipid molecules are found in the cell membrane.

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The empirical formula of any ionic compound can be determined by balancing the charges on the ions to form a neutral compound.

Here are four binary ionic compounds that could be formed from the given ions:

These are just a few examples of binary ionic compounds that could be formed from the given ions.

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The mass of lead based on data is 97.65 grams. The mean atomic mass of lead can be founded in periodic table of elements.

Given:

Therefore:

First, calculate the moles of lead.

[tex]\begin{array}{ll}\sf n &\sf = \dfrac{N}{L}\\\\&\sf = \dfrac{2.84\times 10^{23}}{6.02 \times 10^{23}} \\\\&\sf = 0.471~moles.\end{array}[/tex]

Second, calculate the mass of lead.

[tex]\begin{array}{ll}\sf g&\sf = n \times Ar\\\\&\sf = 0.471 \times 207\\\\&\sf = 97.65~grams.\end{array}[/tex]

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Answer:

Explanation:

Synthesis

2H2 + O2 ---> 2 H2O

Decomposition

CaCO3----> CO2 + CaO

Single replacememt

Na + KCl---> KCl + Na

Double replacement

AgNO3 + NaCl --> AgCl + NaNO3

A) The electric force on the electrons will act downward.

B) So to keep the electrons in a straight line, the magnetic force should act to the left.

C) So the magnetic force on them will be perpendicular to their velocity and will act to the left, as we found in part (b).

D)The magnitude of the magnetic field is 3.64 x 10^-5 T.

To calculate the magnitude of the electric force in newtons, we can use the formula: F = qE where F is the force, q is the charge of the electron, and E is the magnitude of the electric field. The charge of the electron is -1.6 x 10^-19 C, and the magnitude of the electric field is given as E = 5.00 x 10^6 N/C. So we have:

F = (-1.6 x 10^-19 C)(5.00 x 10^6 N/C) = -8.00 x 10^-13 N

Since the electric force is acting downward, we should give it a negative sign to indicate its direction.

To calculate the magnitude of the magnetic field, we can use the formula: F = Bqv where F is the magnetic force, B is the magnitude of the magnetic field, q is the charge of the electron, and v is the speed of the electron. We are given the speed of the electron as 110 m/s, and we know from part (b) that the magnetic force is acting to the left with a magnitude equal to the electric force, so we can set F = 8.00 x 10^-13 N. The charge of the electron is -1.6 x 10^-19 C, so we have:

8.00 x 10^-13 N = B(-1.6 x 10^-19 C)(110 m/s)

Solving for B, we get:

B = 3.64 x 10^-5 T

The given question is incomplete, the complete question is

An electron beam is directed horizontally into a region where there is both an clectric field and a magnetic field. The electrie field points upward and has a magnitude E-SNC, as shown in the figure. While moving through the region the electron beam contine in in a horizontal straight line with speed of 110 ms Otheexpertta.com d d d d - 20% Part() in which direction does the electric force act on the electrons ? Downward Correct 20% Part () In order to keep the electrons in a straight line, in which direction abould the magnetic force on the electrons aet? UV Cerrect! 20** Part() What should the direction of the magnetic field be in order to produce the force described in part (by? Isto the screen Cart! 204 Part (d) Calculate the numerical value of the magnitude of the electric force in newtons F- N Grade Sun Ded Potential 7 E 6 Subs Atem pamp sin COMO tan con atan con sinho cosho tail ) cotando Degrees O Radians 4 3 12 0 pl Tim Harem. Feedki o deductie en 20. Parte) Calculate the magnitude of the magnetic field in telif the electron comes in a horizontal straight line.

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An atom's paramagnetic activity increases with the amount of unpaired electrons in its outermost shell.

According to the atom's quantum mechanical concept, there are specific orbitals, or three-dimensional regions of space, where electrons are more likely to be found. A set of four quantum numbers can be used to describe each electron's characteristics within the quantum atom.

The quantum mechanical or wave mechanical model, on which our current understanding of the atom is based, is one such model. An electron in an atom may only exist in a limited set of states or energies, which is akin to a standing wave.

Consider the number of unpaired electrons in each of the given atoms be: Li-1, N-3, Ni-2 and Te-2

At least one unpaired electron must be present in the valence shell of an atom for it to be paramagnetic. Due to the spin pairing of every electron in their outermost shells, Ba and Hg are not paramagnetic.

An atom's paramagnetic activity increases with the amount of unpaired electrons in its outermost shell.

The complete question is:

One bit of evidence that the quantum mechanical model is "correct" lies in the magnetic properties of matter. Atoms with unpaired electrons are attracted by magnetic fields and thus are said to exhibit Para magnetism. The degree to which this effect is observed is directly related to the number of unpaired electrons present in the atom. Consider the ground-state electron configuration for . Would this atom be expected to be paramagnetic, and how many unpaired electrons are present? It has unpaired electron(s). Consider the ground-state electron configuration for . Would this atom be expected to be paramagnetic, and how many unpaired electrons are present?

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The maximum extensively used initiators produce unfastened radicals (reactive atoms or organizations of atoms that include bizarre numbers of electrons).

Examples encompass peroxides and aliphatic azo compounds used to polymerize vinyl chloride, methyl methacrylate, and different monomers.  Radical polymerization of vinyl monomers (styrene, methyl methacrylate, and vinyl acetate) changed into done in diverse nanochannels of porous coordination polymers (PCPs), wherein relationships among the channel length and polymerization behaviors, which include monomer reactivity, molecular weight, and stereostructure. Radical initiators are applied in business methods which include polymer synthesis. Typical examples are molecules with a nitrogen-halogen bond, azo compounds, and natural and inorganic peroxides.

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Answer:The green elements on the table you are referring to are called Noble gases or Inert gases.

Explanation:

The green elements on the table you are referring to are called Noble gases or Inert gases. They each have two electrons in their outer shell, which gives them a full and stable electron configuration.

The nucleophile in a Friedel-Crafts reaction is the alkyl or acyl group attached to the Lewis acid catalyst.

In a Friedel-Crafts reaction, a Lewis acid catalyst, such as aluminum chloride (AlCl3) or iron(III) chloride (FeCl3), is used to activate an alkyl or acyl halide to make it a better electrophile. The activated alkyl or acyl group then acts as the nucleophile, attacking the aromatic ring of the substrate to form a new carbon-carbon bond.

The overall reaction can be summarized as follows:
R-X + AlCl3 → R+ + AlCl4- (activation of the alkyl or acyl halide)
R+ + Ar-H → Ar-R + H+ (nucleophilic attack on the aromatic ring)

In this reaction, the nucleophile is the R group, which can be an alkyl or acyl group. The Lewis acid catalyst activates the alkyl or acyl halide, making it a better electrophile and allowing it to attack the aromatic ring.

The end result is the formation of a new carbon-carbon bond between the alkyl or acyl group and the aromatic ring.

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Vinegar (acetic acid) and baking soda (sodium bicarbonate) react in an endothermic reaction to produce sodium acetate, carbon dioxide, and water. The statement that justifies classifying the reaction as endothermic is  The total potential energy of the products is less than the total potential energy of the reactants. The correct answer is D.

An endothermic process is one in which the heat of the system increases as a result of absorbing heat from the environment and transferring it to the system. The reactants have higher potential energy than the products.

Baking soda and vinegar react by absorbing heat from the surrounding environment, resulting in the production of carbon dioxide, sodium acetate, and water.

The reactants in this kind of reaction absorb heat, increasing their potential energy, which is high in comparison to the potential energy of the products created.

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Dr. James Jerger, collaborated to develop the digital hearing aid

The development of the digital hearing aid was the result of a collaboration between several individuals and organizations. One of the key figures in the development of digital signal processing technology, which forms the basis of modern digital hearing aids, was Thomas Stockham, a physicist and engineer who worked at the Massachusetts Institute of Technology (MIT) in the United States.

In the years since the first digital hearing aids were developed, many other researchers, engineers, and clinicians have contributed to the ongoing development and refinement of these devices. Today, digital hearing aids are widely used around the world and have helped millions of people with hearing loss to improve their communication and quality of life.

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The most common way to express solution concentration is the molarity

The molality of a solution is uniform to the moles of solute divided by the mass of solvent in kilograms, while the molarity of a solution is alike to the moles of solute divided by the volume of solution in liters.

Molarity is the number of moles of solute per liter of solution. For example, if you dissolve table salt in water, salt is the solute, and water is the solution. One mole of sodium chloride weighs 58.44 grams. If you diffuse 58.44 grams of NaCl in one liter of water, you have a one-molar solution, reduced to 1M

So we can conclude that Molarity is defined as the integer of moles of solute per liter of solution.

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The O- group is a special type of oxygen-containing functional group called an ether. The oxygen atom of the ether group is bonded to two carbon atoms, so the IR absorption frequency for this functional.

Carbon atoms are the basic building blocks of organic molecules and are essential to all known forms of life. Carbon atoms are a unique element because they have the ability to form strong bonds with other elements, such as hydrogen, oxygen and nitrogen. This allows them to form an incredibly wide variety of molecules, from simple sugars to complex proteins.

1. Ethanol (Alcohol): C3H6O

Functional Group: OH (Hydroxyl), IR Absorption Frequency: 3350 cm-1

2. Acetone (Ketone): C3H6O

Functional Group: C=O (Carbonyl), IR Absorption Frequency: 1715 cm-1

3. 2-Propanol (Alcohol): C3H6O

Functional Group: OH (Hydroxyl), IR Absorption Frequency: 3350 cm-1

4. Dimethyl Ether (Ether): C3H6O

Functional Group: O- (Ether), IR Absorption Frequency: 1090 cm-1

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The principal quantum number is n = 4. Angular momentum quantum number l = 3. The number of degenerate orbitals based on the magnetic quantum number is 7 . The number of radial nodes is 0 .

maximum number of electrons in the entire shell are 14.

The 4f orbital is a sublevel of the fourth energy level, so the principal quantum number is n = 4.

The angular momentum quantum number, l, is equal to 3 for the f subshell. This means that the electrons in the 4f orbital have l = 3.

For the magnetic quantum number, ml, the range is -l to +l, so for the 4f orbital, there are 2l + 1 = 7 possible values of ml (-3, -2, -1, 0, 1, 2, 3), which means there are 7 degenerate orbitals.

The number of radial nodes can be calculated using the formula n - l - 1, so for the 4f orbital, there are (4 - 3 - 1) = 0 radial nodes.

The maximum number of electrons in the entire shell can be determined using the formula 2n^2, where n is the principal quantum number. For n = 4, the maximum number of electrons in the 4th shell is 2(4)^2 = 32. However, since the 4f orbital is a sublevel within the 4th shell, the maximum number of electrons that can occupy the 4f orbital is given by the Pauli exclusion principle, which states that no two electrons in an atom can have the same set of four quantum numbers. Therefore, the maximum number of electrons that can occupy the 4f orbital is 2 x 7 = 14.

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The monomer that can conceivably form isotactic polymers is [tex]C=CH_2 CH_3[/tex]. Option (d) is correct.

Isotactic polymers are stereoregular polymers in which all the substituents in each repeating unit are on the same side of the polymer chain. The vinyl monomer [tex]C=CH_2 CH_3[/tex] has a relatively simple structure that can pack efficiently and promote isotactic polymerization.

For example, monomer (a) has no chirality center and no stereoisomers, so it cannot form isotactic polymers. Monomer (b) and (c) have chirality centers, but their structures are more complex, making it more difficult to achieve isotactic polymerization. Monomer (e) has multiple chirality centers and can form stereoisomers, but it is not a vinyl monomer and is less likely to form isotactic polymers.

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--The complete question is, Which of the following monomers can conceivably form isotactic polymers?--

3-methyl-2-Pentene is the correct answer. 3-methyl-2-pentene is an alkene with a molecular formula of C_5H_10. It is a colorless liquid with a pungent odor.

Alkenes are a class of organic compounds that contain a carbon-carbon double bond. They are unsaturated hydrocarbons, meaning that they have fewer hydrogen atoms than their corresponding saturated hydrocarbons.

The general formula for an alkene is Cn[tex]H_{2}[/tex]n, where "n" represents the number of carbon atoms in the molecule. The simplest alkene is ethene, which is also called ethylene and has the chemical formula [tex]C_{2} H_{4}[/tex]. Alkenes are important intermediates in many industrial processes and are used in the production of a variety of products including plastics, synthetic rubber, and solvents.

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Earlier calculations were made because the ion product (IP) is bigger than the Ksp value. [tex](1.5625 \times 10-9)[/tex] A precipitate will occur because the solution is supersaturated with PbI2.

Ions are atoms or molecules that have an unequal number of electrons and protons, resulting in a net electrical charge.

Atoms are electrically neutral because they normally include an equal number of positively and negatively charged protons and electrons. Yet, an atom becomes an ion and acquires electrical charge when it absorbs or loses one or more electrons.

The solubility product constant (Ksp) expression for lead (II) iodide (PbI2) is:

[tex]Ksp = [Pb2+][I-]^2[/tex]

We know the concentration of I- is [tex]1.25 \times 10-3 M[/tex] When the solution is saturated, but we don't know the concentration of Pb2+.

However, we can assume that the solubility of PbI2 is low and that the concentration of Pb2+ is much less than [tex]1.25 \times 10-3 M[/tex]. Therefore, we can use the concentration of I- to calculate the Ksp as follows:

[tex]Ksp = [Pb2+][I-]^2[/tex]

[tex]Ksp = x(1.25\pm \times 10-3)^2[/tex]

[tex]Ksp = 1.5625 \pm \times 10-9x[/tex]

using this Ksp value, we must ascertain whether a precipitate will occur when 350 mL of [tex]5.5 \times 10-2 M[/tex] 250 mL of lead (II) nitrate (Pb(NO3)2) and

[tex]4.8 \times 10-2[/tex] M iodide of sodium (NaI).

We must first figure out the original Pb2+ and I- concentrations in the combined solution. Since [tex]Pb(NO3)^2[/tex]is a potent electrolyte that totally dissociates into the ions Pb2+ and NO3- in water. Hence, the initial Pb2+ concentration is:

[tex][Pb2+] = (5.5 \times 10-2 M) \times (0.350 L/0.6 L) = 3.208 \times 10-2 M[/tex]

Similar to this, NaI totally separates into Na+ and I- ions in water due to its strong electrolyte nature. As a result, I- has the following initial concentration:

[tex][I-] = (4.8 \times 10-2 M) \times (0.250 L/0.6 L) = 2.000 \times 10-2 M[/tex]

Now determine the mixed solution's PbI2 ion product (IP) as follows.

[tex]IP = [Pb2+][I-]^2[/tex]

[tex]IP = (3.208 \times 10-2 M)(2.000 \times 10-2 M)^2[/tex]

[tex]IP = 2.563 \times 10-8[/tex]

Therefore, the ion product (IP) exceeds the Ksp value that we previously determined. [tex](1.5625 \times 10-9)[/tex], a precipitate will form because the solution is supersaturated with PbI2.

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The wavelength (in nanometers) of a photon emitted by a hydrogen atom when its electron drops from the n = 5 to n = 3 state is 1280nm.

The distance between two subsequent crests or troughs of the wave is what is meant by the term wavelength. Lambda () is a Greek letter that stands for wavelength.

The wavelength is the distance between one wave's "crest" to another wave's "crest." We can calculate the wavelength by comparing the "trough" of one wave to the "trough" of another wave.

These are the calculations for the energy (E) difference between two shells:

ΔE = -RH [(1 / nf2) - (1/ni2)] ΔE

R Rydberg’s constant (1.0973731568539(55)×107m−1)

nf and ni Integers where n2>n1.

ΔE = -RH [(1 / nf2) - (1/ni2)] ΔE

= -2.18 x10-18 J [(1/32) - (1/52)] ΔE

= -1.55 x10-19 JE

hc/λλ = hc/Eλ

where

λ =The wavelength of the photon.

hc/λλ = hc/Eλ

= [(6.63 x10-34 J.s.) x (3.00 x1017 nm/s)] /(1.55 x10-19 J)

λ = 1280nm

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The statement that correctly describes the quantum number n is, "an electron with n = 2 is at a higher energy level than any other energy levels.

Generally, the set of numbers that is used to locate the position and energy of the electron in an atom are known as quantum numbers. Basically, there are four types of quantum numbers, which are named as, principal, azimuthal, magnetic and spin quantum numbers.

In any atom, there are a total of four quantum numbers: the principal quantum number (n), the orbital angular momentum quantum number (l), the magnetic quantum number (ml), and the electron spin quantum number (ms) which generally describes the characteristic properties of an atom.

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The structure is consistent with this 'H NMR spectrum is CH;OCCH;. Option a is correct answer.

The 'H NMR spectrum doesn't provide enough information to definitively determine the structure of the molecule. However, based solely on given options, the structure that is most consistent with the chemical shift of the proton signal at around 3.7 ppm is option A, CH3OC(=O)CH2CH3.

This is because the chemical shift of the proton on the OCH3 group is typically found in this region, and the presence of the carbonyl group would also affect the chemical shift of nearby protons. However, additional spectroscopic data and/or chemical tests may be necessary to confirm the structure.

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--The complete question is, Which structure is consistent with this 'H NMR spectrum? CH;OCCH; (B) COCH;CH; (C) OCCH,CH; (D) OCCH; CH;--

The curved arrow representation for the provided resonance structure is attached.

The negative charge (lone pair) is moved towards the hybridized carbon and the pi electrons also move towards another carbon, so the delocalization takes place and forms new C=O, C=C bond, and then oxygen atom gets the negative charge.

The lone pairs on nitrogen atom moved to the hybridized carbon and another pi bond moves towards the oxygen atom. This is shown with the curved arrows.

Note that necessary diagrams are attached.

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The balanced equation of the reaction is option d. The  limiting reactant here is KBr and excess reactant is calcium nitrate. The percent yield of the reaction is 93 %.

The limiting reactant in a reaction is the reactant which is fewer in amount and as soon it is consumed, the reaction stops. For the given reaction, option d is the balanced chemical equation.

One mole of calcium nitrate requires 2 moles of KBr.

molar mass of calcium nitrate = 164 g/mol

no.of moles in 75 g = 75/164 = 0.457

molar mass of KBr = 118.9 g/mol

no.of moles 95 g = 95/118.9 = 0.798

0.457 moles of calcium nitrate needs its twice amount that is 0.9 moles of KBr. Hence, KBr is the limiting reactant and calcium nitrate is excess reactant here.

2 moles or 237.8 g of KBr gives 2 moles or 202 g of potassium nitrate. Then, 95 g of KBr will gives:

(95×202)/237.6 = 81.3 g

actual yield = 75.75 g

then percent yield  = 75.75 /81.3 × 100 = 93 %.

0.79 moles of KBr needs its half or 0.399 moles of calcium nitrate. But we have 0.45 moles. Thus, excess amount is

(0.45 - 0.399) × 164 g/mol = 9.5 g.

Therefore, the 9.5 g of excess reactant will be left over.

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