5. Calculate the goniometer setting, in terms of 2θ, required to observe the Lβ1 (n=1) lines for Br at λ = 8.126Å when the diffracting crystal is:a) Ethylenediamine d-tartrate (d=4.404Å)b) Ammonium dihydrogen phosphate (d=7.549Å)

A scientific theory is a well-tested explanation for a widely accepted hypothesis.

A scientific theory is a coherent statement or set of ideas that explains observed facts or phenomena and correctly predicts new facts or phenomena not previously observed, or which sets out the laws and principles of something known or observed.

In summary, a theory is a hypothesis confirmed by observation or experiment.

A body of facts that have been repeatedly confirmed through observation and experiment is said to be a theory.

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The names of the positions are called:

(1) (10) Atomic number

(2) (11) Chemical symbols

(3) (12) Elements

(4) (13) Atomic mass

Atomic structure refers to the composition and arrangement of subatomic particles within an atom. An atom consists of a central nucleus, which contains positively charged protons and uncharged neutrons, surrounded by negatively charged electrons that move around the nucleus in shells or energy levels.

The number of protons in the nucleus determines the atomic number and thus the identity of the element. The arrangement of electrons around the nucleus determines the chemical and physical properties of the element.

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The questions are:

10 What is the name for the number in this position called? (the answer is not "6") →6

11 What is the name for the letter in this position called? (the answer is not "C"!) →C

12 What is the name in this position called? (the answer is not "Carbon"!) →Carbon

13

What is the name for the number in this position? (the answer is not "12.0") →12.0

Use the spaces below to type your answers to the questions above.

Answer:

2.16 M

Explanation:

The molarity of the solution is 2.16 M. To calculate the molarity, you need to first determine the number of moles: 29.4 grams of NaCl is equal to 0.737 moles. Then, divide the number of moles, 0.737, by the volume of the solution, which is 250 mL. Multiplying the result by 1000 gives the molarity, which is 2.16 M.

yw

Base: Water, b. [tex]HCN[/tex] Acid Base [tex]OH-[/tex] , c. Base: I- Acid:[tex]HgI2[/tex] . Chemical substances known as acids have the ability to donate a proton [tex](H+)[/tex] to a base or another molecule.

Chemical substances known as acids have the ability to donate a proton [tex](H+)[/tex]  to a base or another molecule. They have a sour flavour, have the power to dissolve metals, and can make litmus paper turn red. On the pH scale, where 7 is neutral and lower numbers indicate higher acidity, acids have a pH below 7. Hydrochloric acid, sulfuric acid, and acetic acid are a few typical examples of acids. Acids are essential for many chemical processes, such as digestion, the creation of energy, and the synthesis of numerous significant chemicals. Also, they are employed in a number of sectors, such as industry, food production, and agriculture.

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Taking into account the definition of dilution, if chemist must dilute 93.1 mL of 7.79 of uM aqueous mercury (I) chloride solution until the concentration falls to 3.00 uM, the final volume is 0.24175 L.

Dilution is a procedure by which the concentration of a solution is lowered, usually with the addition of a diluent.

In a dilution the amount of solute does not change, but as more solvent is added, the concentration of the solute decreases, as the volume of the solution increases.

A dilution is mathematically expressed as:

Ci×Vi = Cf×Vf

where

In this case, you know:

Replacing in the definition of dilution:

7.79 uM× 93.1 mL= 3 uM× Vf

Solving:

(7.79 uM× 93.1 mL)÷ 3 uM= Vf

241.75 mL= 0.24175 L = Vf (being 1000 mL= 1 L)

In summary, the final volume is 0.24175 L.

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Substance       intermolecular force

CH2OH   --->   Hydrogen bonding

CH3F       -->    Dipole-dipole forces

C3H8       -->    Dispersion forces

CaCL2      -->   Ionic bonding

The intermolecular force present in CH2OH is hydrogen bonding. The intermolecular force present in CH3F is  Dipole-dipole forces. Ionic bonding is defined as a type of chemical bonding that involves the electrostatic attraction between oppositely charged ions or between two atoms with sharply different electronegativities. It is the primary interaction occurring in ionic compounds. Hydrogen bonding results from the attractive force between a hydrogen atom covalently bonded to a very electronegative atom such as a N, O, or F atom and another very electronegative atom.

Dipole-dipole forces are defined as a attractive forces between the positive end of one polar molecule and the negative end of another polar molecule.  Dispersion force is defined as a temporary attractive force that results when the electrons in two adjacent atoms occupy positions that make the atoms form temporary dipoles.

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The complete question is,

Match each substance correctly to the principal type(s) of intermolecular force(s) present, other than covalent bonding.

CH2OH          Ionic bonding

CH3F              Hydrogen bonding

C3H8              Dispersion forces

CaCL2            Dipole-dipole forces

Answer:

The mass of 2 moles of carbon tetrachloride is

307.646 grams

Explanation:

The chemical formula for Carbon tetrachloride is [tex]\ce{CCl_4}[/tex].  It contains 1 carbon atom and 4 chlorine atoms.

Carbon tetrachloride is formed due to the covalent bond between one carbon atom with four chlorine atoms.

In order to find the mass of 2 moles of [tex]\ce{CCl_4}[/tex] we need to determine the molar mass.

The molar mass of carbon is 12.011 g/mol.

The molar mass of chlorine is 35.453 g/mol.

As stated before we have 1 carbon atom and 4 chlorine atoms. So the molar mass can be evaluated by

[tex]\left(1*12.011\right)+\left(35.453*4\right)=153.823[/tex]

The molar mass of [tex]\ce{CCl_4}[/tex] is 153.823 g/mol.

You can multiply that by 2 to get the mass in grams of 2 moles of carbon tetrachloride.

[tex]2*153.823 =307.646[/tex]

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The formation of the phosphorylated intermediate (an anhydride) involves the formation of a penta-coordinate intermediate. This intermediate is formed by a nucleophilic attack of the sulfur on the phosphorus atom of the phosphate group.

In this mechanism, the sulfur atom of the sulfate group nucleophilically attacks the phosphorus atom of the phosphate group to form a penta-coordinate intermediate. This intermediate then rearranges to form a phosphorylated intermediate, which is an anhydride.

Mechanism showing the penta-coordinate intermediate and the formation of the phosphorylated intermediate are given as follows:

Step 1: Alkyl Phosphate Formation : The first step of the mechanism includes the formation of an alkyl phosphate. A proton is abstracted by OH− from the phosphate group to create the alkyl phosphate. The base catalyzes this step.

Step 2: Binding to Mg2+After the alkyl phosphate is created, the magnesium ion binds to it.

Step 3: Nucleophilic attack: Following that, the nucleophilic attack happens, with the nucleophile being the water molecule. It is coordinated with the magnesium ion. It occurs at phosphorus, causing it to be phosphorylated. It results in the creation of a pentacoordinate intermediate.

Step 4: Release of Orthophosphate: Orthophosphate is released as a result of the reaction between pentacoordinate intermediate and water. It results in the creation of a diester intermediate.

Step 5: Subsequent Hydrolysis: In the final step, the intermediate diester is hydrolyzed to form orthophosphate and the final product. This is accomplished via nucleophilic substitution.

The end result is a free phosphate group that is bound to the alcohol's oxygen. A phosphate anhydride is formed in the process.

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The correct answer is option D, It can affect the AH value.

A phase change is a physical change in a substance in which the substance's state of matter is changed, such as from a gas to a liquid or from a liquid to a solid. It is also known as a phase transition.

Phase changes also involve changes in energy, temperature, and pressure. For example, when a solid melts to become a liquid, it absorbs energy and the temperature rises. When a liquid boils to become a gas, energy is released and the temperature decreases. Similarly, when a gas condenses to become a liquid, energy is released and the pressure increases.

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Answer: The Oxidation State Of Sulphur is +6

Explanation:

The original concentration of the H₂C₂O4 solution is 0.7455 mol/L.

The balanced chemical equation for the reaction between H₂C₂O4 and NaOH is:

H₂C₂O4 + 2NaOH → Na₂C₂O₄ + 2H₂O

From this equation, we can see that the acid reacts with the base in a 1:2 ratio, meaning that one mole of H₂C₂O4 will react with two moles of NaOH.

To find the original concentration of the acid solution, we need to use the formula for calculating molarity:

Molarity = moles of solute / volume of solution (in liters)

We can start by calculating the number of moles of NaOH used in the titration:

moles of NaOH = Molarity x volume of NaOH used (in liters)

moles of NaOH = 0.4700 mol/L x 0.05820 L

moles of NaOH = 0.027354 moles

Since the acid and base react in a 1:2 ratio, we know that the number of moles of H₂C₂O4 is half the number of moles of NaOH used:

moles of H₂C₂O4 = 0.027354 moles / 2

moles of H₂C₂O4 = 0.013677 moles

Now we can use the formula for molarity to calculate the original concentration of the acid solution:

Molarity of H₂C₂O4 = moles of H₂C₂O4 / volume of H₂C₂O4 used (in liters)

Molarity of H₂C₂O4 = 0.013677 moles / 0.01835 L

Molarity of H₂C₂O4 = 0.7455 mol/L

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The enthalpy change can not be measured directly because you have to take into account how much energy was put into the reaction in the first place.

Hope this helps!!! :)

The standard enthalpy of formation of all elements in their standard states are assumed to be zero. It is not possible to determine the enthalpy of formation of calcium carbonate as it is formed from other compounds.

The standard enthalpy of formation of a compound can be defined as the enthalpy change accompanying the formation of one mole of the compound from its constituent elements, all the substances being in their standard states.

The standard enthalpy of formation is usually denoted as ΔfH⁰. For example the enthalpy of formation of CO₂ and CH₄ are -393.5 kJ mol⁻¹ and -74.8 kJ mol⁻¹ respectively.

Here CaCO₃ is formed by the reaction:

CaO + CO₂ → CaCO₃

The enthalpy change for the given reaction is not an enthalpy of formation of CaCO₃. Since CaCO₃ is not formed from its constituent elements.

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Moles of magnesium = 0.198 g / 24.31 g/mol = 0.00815 mol

What are the moles?

Based on the given data, we can calculate the moles of magnesium using the following formula:

moles of magnesium = mass of magnesium (g) / molar mass of magnesium

The molar mass of magnesium is 24.31 g/mol.

Thus, moles of magnesium = 0.198 g / 24.31 g/mol = 0.00815 mol

It seems that the experiment involves determining the mass and moles of magnesium. The temperature of water, vapor pressure of water, and barometric pressure are likely additional data points collected during the experiment for further analysis.

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In the stepwise formation of [Cu(NH3)4]2 from [Cu(H2O)4]2, [Cu(NH3)4]2+ is formed in the second step.

A coordination compound is formed by the combination of a central metal ion or atom and one or more ligands. The central metal ion or atom is typically positively charged, and the ligands are generally negatively charged or uncharged molecules or ions that have at least one electron pair accessible for coordination.

The coordination complex is represented by a square bracket around the central metal ion, and the ligands are connected to it with a comma.Copper(II) sulfate (CuSO4) is a well-known example of a coordination compound. The Cu2+ ion is the central metal ion, and the four H2O molecules are the ligands in this case. It is represented as [Cu(H2O)4]2+.

In the stepwise formation of [Cu(NH3)4]2 from [Cu(H2O)4]2, the following steps are involved:In the first step, four H2O molecules are replaced by four NH3 molecules. The product of this step is [Cu(NH3)4(H2O)2]2+.The second step is the replacement of the remaining two H2O molecules by NH3.

This step produces the desired [Cu(NH3)4]2+ coordination compound.In short, the copper ion in [Cu(H2O)4]2+ loses two H2O molecules and gains four NH3 molecules, forming [Cu(NH3)4(H2O)2]2+. Then, two more H2O molecules are replaced by NH3, resulting in the formation of [Cu(NH3)4]2+. Therefore, [Cu(NH3)4]2+ is formed in the second step.

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21.16 mL of 0.250 M HNO3 is required to titrate (neutralize) a solution containing 0.297 g of KOH.

To solve this problem, we need to use the balanced chemical equation for the reaction between HNO3 and KOH, which is:

HNO3 + KOH → KNO3 + H2O

From the equation, we can see that one mole of HNO3 reacts with one mole of KOH.

First, we need to determine the number of moles of KOH in 0.297 g of KOH:

mass of KOH = 0.297 g

molar mass of KOH = 56.11 g/mol

number of moles of KOH = mass/molar mass = 0.297 g/56.11 g/mol = 0.00529 mol

Since one mole of HNO3 reacts with one mole of KOH, we need 0.00529 moles of HNO3 to neutralize the KOH.

Now, we can use the molarity and the number of moles of HNO3 to calculate the required volume of HNO3:

Molarity of HNO3 = 0.250 M

Number of moles of HNO3 = 0.00529 mol

Volume of HNO3 = Number of moles of HNO3/Molarity of HNO3

Volume of HNO3 = 0.00529 mol/0.250 mol/L

The volume of HNO3 = 0.02116 L or 21.16 mL

Therefore, 21.16 mL of 0.250 M HNO3 is required to titrate (neutralize) a solution containing 0.297 g of KOH.

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The correct reaction equation is; Sr(OH)2 ----> Sr + 2OH

A correct chemical reaction equation must follow the law of conservation of mass, which states that matter cannot be created or destroyed, only transformed from one form to another. This means that the total number of atoms of each element on the reactant side of the equation must be equal to the total number of atoms of each element on the product side.

To ensure that an equation is correct, you should first check that the chemical formulas of the reactants and products are correct. You can then balance the equation by adjusting the coefficients in front of each chemical formula so that the number of atoms of each element is the same on both sides of the equation.

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The formula for Co3+ is Co3+ because it represents the ion of cobalt that has lost three electrons, leaving it with a 3+ charge.

What is chemical formula and how they are formed ?

A chemical formula is a symbolic representation of a chemical compound that shows the types of elements present in the compound and the relative number of atoms of each element. For example, the chemical formula for water is H2O, which indicates that it is made up of two hydrogen atoms and one oxygen atom.

Chemical formulas are formed by identifying the elements that make up a compound and determining the relative number of each element in the compound. The number of each element is represented by a subscript following the chemical symbol of the element. For example, the chemical formula for methane is CH4, which indicates that there is one carbon atom and four hydrogen atoms in each molecule of methane.

The formula for Se2- is Se2- because it represents the ion of selenium that has gained two electrons, giving it a 2- charge.

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Answer:

The correct electron dot diagram for Al is option A:

•Al:

:AI:

Explanation:

Answer: Polar

Explanation: This is because if you look up the Lewis Dot structure of this specific molecule, it will have some net dipole moment, which makes it polar.

It can be considered that when a molecule does have some net dipole moment, it is polar.

So, yes CF3Cl is polar.

CF₃Cl, also known as chlorotrifluoromethane, is a polar molecule.

To determine the polarity of a molecule, consider the individual bond polarities and the molecular geometry.

In CF₃Cl, there is a difference in electronegativity between carbon (C) and chlorine (Cl), as well as between carbon and fluorine (F). Chlorine and fluorine are more electronegative than carbon, meaning they have a greater ability to attract electrons toward themselves.

The C-Cl bond and the C-F bonds in CF₃Cl are polar bonds due to the electronegativity difference. The Cl and F atoms pull the shared electrons towards themselves, creating partial negative charges on those atoms and partial positive charges on the carbon atom.

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The mass of benzene that should be dissolved in 425g of water at 35°C to produce a solution with a vapor pressure of 36.1 mmHg is approximately 10.02 g.

1. Calculate the mole fraction of benzene (Xbenzene) in the solution using the following equation:

Ptotal = Xbenzene x P0benzene + Xwater x P0water

where Ptotal is the total vapor pressure of the solution, P0benzene is the vapor pressure of pure benzene, P0water is the vapor pressure of pure water, and Xwater = 1 - Xbenzene.

Rearranging the equation to solve for Xbenzene:

Xbenzene = (Ptotal - Xwater x P0water) / P0benzene

Substituting the given values:

Xbenzene = (36.1 mmHg - 0.953 x 42.2 mmHg) / 95.1 mmHg

Xbenzene = 0.390

2. Calculate the molality of the solution using the following equation:

molality = moles of solute / mass of solvent in kg

moles of solute = molality x mass of solvent in kg

Substituting the given values:

molality = 0.390 mol / kg

mass of solvent = 425 g = 0.425 kg

moles of solute = 0.390 mol / kg x 0.425 kg

moles of solute = 0.166 mol

3. Calculate the mass of benzene using its molar mass:

mass of benzene = moles of benzene x molar mass of benzene

Substituting the given values:

moles of benzene = 0.166 mol

molar mass of benzene = 78.11 g/mol

mass of benzene = 0.166 mol x 78.11 g/mol

mass of benzene = 12.97 g

However, we assumed that the density of the solution is equal to the density of water, which is not the case. Therefore, we need to adjust the mass of benzene by using the following equation:

mass of benzene = mass of solute / (1 - mass fraction of solute)

4. Calculate the mass fraction of benzene using the mole fraction:

mass fraction of benzene = (Xbenzene x molar mass of benzene) / (Xbenzene x molar mass of benzene + Xwater x molar mass of water)

5. Substituting the given values:

molar mass of water = 18.02 g/mol

mass fraction of benzene = (0.390 x 78.11 g/mol) / (0.390 x 78.11 g/mol + 0.610 x 18.02 g/mol)

mass fraction of benzene = 0.097

Substituting the values in the mass equation:

mass of benzene = 12.97 g / (1 - 0.097)

mass of benzene = 10.02 g

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The following statements about the ionization of the side chain of glutamine in water is true are Glutamine has a positively charged form with a pK, around 10, Glutamine is usually deprotonated but will gain a proton at low pH, Glutamine is usually protonated but will lose a proton at high pH.

Glutamine is an amino acid that is considered to be a critical nutrient for cell growth and division, as well as protein synthesis. It is an amino acid that is commonly found in proteins, which are essential components of the human body. Glutamine is an amino acid that contains an amide group and an acidic side chain, making it a polar and hydrophilic amino acid. It has a chemical formula of [tex]C_{5}H_{10}N_{2}O_{3}[/tex].

Ionization is the process of removing or adding one or more electrons from an atom or molecule, giving it a net electrical charge. When an atom loses one or more electrons, it becomes positively charged, whereas when it gains one or more electrons, it becomes negatively charged.

The pH is a measure of acidity or basicity in a solution, with a scale ranging from 0 to 14. A pH of 7 is considered neutral, while anything below 7 is acidic and anything above 7 is basic. The term "pH" refers to "power of hydrogen." It represents the concentration of hydrogen ions in a solution. The lower the pH, the higher the concentration of hydrogen ions, and the higher the acidity.

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All of the groups of substances involve the use of chemicals from the question that we have here.

Chemicals are essential to life and to many industries, including agriculture, medicine, manufacturing, and technology. They can be found in everyday objects such as food, clothing, electronics, and cleaning products.

Chemicals can be classified into various categories based on their properties, chemical structure, and uses. Some common categories of chemicals include:

Elements: Pure substances that cannot be broken down into simpler substances. Examples include carbon, oxygen, and gold.

Compounds: Substances composed of two or more elements chemically bonded together. Examples include water (H2O) and table salt (NaCl).

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Which of the following groups of substances involve the use of chemicals? Indicate all that apply.

Check all that apply.

Which of the following groups of substances involve the use of chemicals? Indicate all that apply.Check all that apply.

A light-weight bicycle frame, food packaging, a car exhaust catalytic converter

Soap, shampoo, washing powder

Antiseptic cream, pain killers, energy drinks

Paints, printer toner, food coloring

Computer displays, LED lights, barcode readers

(a) one radial node the Number of radial nodes = n - l - 1

And number of angular nodes = l

n = 3 and l = 1

Orbital is 3p.

(b) It has zero angular node hence s-orbital and there is 1 radial node . 1 = n - 0 - 1 ; n = 2 and l = 0

The orbital is 2s.

(c) the shape of the orbital is that of dz². There is two angular nodes and there is no radial node.

n = 3 and l = 2

Hence the orbital is 3dz².

In atomic physics, a radial node is a point in space where the probability density of finding an electron in an atom is zero. It is a type of nodal plane that occurs in atomic orbitals, which are regions of space where electrons are most likely to be found.

Radial nodes occur in the radial distribution function of an atomic orbital, which describes the probability density of finding an electron at a given distance from the nucleus. The number of radial nodes in an atomic orbital is equal to n - l - 1, where n is the principal quantum number and l is the azimuthal quantum number.

Radial nodes represent regions of space where the radial wave function of the electron changes sign.

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The hydronium ion concentration, [H+] of a solution with a pH of 6.82 is 1.51 × 10-⁷ M.

The hydrogen or hydronium ion concentration of a solution can be calculated from the pH using the following formula;

pH = - log {H+}

[H+] = 10−pH

by exponentiating both sides with base 10, we can "undo" the common logarithm.

{H+} = 10-⁶.⁸²

{H+} = 0.000000151356

[H+] = 1.51 × 10-⁷ M

Therefore, the hydronium ion concentration with a pH of 6.82 is 1.51 × 10-⁷ M.

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Answer: Cleavage

Explanation:

When a mineral breaks along a weekly bonded plane it is called cleavage

Answer:

Explanation:

The lattice energy (LE) of MgCl₂ can be calculated using the Born-Haber cycle, which relates the lattice energy to other thermodynamic quantities such as enthalpy of sublimation, ionization energy, electron affinity, and heat of formation.

The equation for the lattice energy of MgCl₂ is:

LE(MgCl₂) = H(sublimation of Mg) + IE(Mg) + EA(Cl) + 1/2 H₂(Cl₂) - DH(f)(MgCl₂)

where H(sublimation of Mg) is the enthalpy of sublimation of Mg, IE(Mg) is the ionization energy of Mg, EA(Cl) is the electron affinity of Cl, H₂(Cl₂) is the heat of formation of Cl₂, and DH(f)(MgCl₂) is the heat of formation of MgCl₂.

We are given the following equations:

Mg(g) → Mg2+(g) + 2 e ΔH₁ = +2188 kJ/mol

Cl(g) + e → Cl-(g) ΔH₂ = -337 kJ/mol

Mg(s) + Cl₂(g) → MgCl₂(s) ΔH₃ = -642 kJ/mol

Using these equations, we can calculate the values of H(sublimation of Mg), IE(Mg), EA(Cl), H₂(Cl₂), and DH(f)(MgCl₂) as follows:

H(sublimation of Mg) = ΔH₂(Mg(g)) + 1/2 ΔH₃(Cl₂(g)) - ΔH₁(Mg2+(g)) = -2220 kJ/mol

IE(Mg) = ΔH₁(Mg(g)) = +2188 kJ/mol

EA(Cl) = ΔH₂(Cl(g)) = -337 kJ/mol

H₂(Cl₂) = 0 (since Cl₂ is in the gas phase)

DH(f)(MgCl₂) = ΔH₃(Mg(s), Cl₂(g), MgCl₂(s)) = -642 kJ/mol

Substituting these values into the equation for the lattice energy, we get:

LE(MgCl₂) = -2220 + 2188 - 337 + 1/2(0) - (-642) = -3509 kJ/mol

Therefore, the lattice energy of MgCl₂ is approximately -3509 kJ/mol.

Answer:

The solution in the test tube would turn pink earlier with the more concentrated NaOH solution.

This is because the concentration of the NaOH solution is directly proportional to the number of moles of NaOH per unit volume of the solution.

So, with a more concentrated NaOH solution (1.0 M compared to 0.5 M), each mL of NaOH solution contains twice as many moles of NaOH.

Therefore, it would take half as much volume (i.e., 12.4 mL instead of 24.8 mL) of the 1.0 M NaOH solution to react with the same number of moles of the unknown acid as the 0.5 M NaOH solution.