What quantity in moles of precipitate are formed when 52.9 mL of 0.400 M Ca(NO₃)₂ is mixed with excess K₃PO₄ in the following chemical reaction?
3 Ca(NO₃)₂(aq) + 2 K₃PO₄(aq) → Ca₃(PO₄)₂(s) + 6 KNO₃(aq)

4.69 g of oxygen gas is consumed by the reaction of 2.0 g of ammonia.

What is Atomic Mass?

Atomic mass is the mass of an atom of a chemical element, expressed in atomic mass units (amu). It is a measure of the total number of protons and neutrons in the nucleus of an atom. The atomic mass is usually given relative to the mass of a carbon-12 atom, which is assigned a mass of exactly 12 atomic mass units.

The balanced chemical equation for the reaction is:

4NH3 + 5O2 → 4NO + 6H2O

From the equation, we can see that 4 moles of NH3 reacts with 5 moles of O2. We need to determine how many moles of NH3 we have, and then use the mole ratio to calculate the number of moles of O2 needed.

First, we calculate the number of moles of NH3:

moles of NH3 = mass of NH3 / molar mass of NH3

moles of NH3 = 2.0 g / 17.03 g/mol (molar mass of NH3)

moles of NH3 = 0.1174 mol

Now we use the mole ratio from the balanced chemical equation to calculate the number of moles of O2:

moles of O2 = (5/4) x moles of NH3

moles of O2 = (5/4) x 0.1174 mol

moles of O2 = 0.1468 mol

Finally, we can use the number of moles of O2 to calculate the mass of O2 consumed:

mass of O2 = moles of O2 x molar mass of O2

mass of O2 = 0.1468 mol x 32.00 g/mol (molar mass of O2)

mass of O2 = 4.69 g

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The molarity of a solution made by dissolving 75 g of Epsom salt in 2.3 liters of solution would be 0.27 M.

The first step in calculating the molarity of the solution is to determine the number of moles of MgSO4 dissolved in 2.3 liters of solution.

The molar mass of MgSO4 is:

24.31 g/mol (for Mg) + 32.06 g/mol (for S) + 4x16.00 g/mol (for 4 O) = 120.37 g/mol

The number of moles of MgSO4 can be calculated using the formula:

moles = mass / molar mass

moles = 75 g / 120.37 g/mol = 0.623 moles

Next, we need to calculate the molarity (M) of the solution, which is defined as the number of moles of solute (MgSO4) per liter of solution:

Molarity = moles of solute / liters of solution

Molarity = 0.623 moles / 2.3 L = 0.27 M

Therefore, the molarity of the solution made by dissolving 75 g of Epsom salt (MgSO4) in 2.3 Liters of solution is 0.27 M.

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Answer:

A 3.0 M solution of NaOH has 3.0 moles of NaOH per liter of solution. There are 0.25 L of solution (250mL⋅1L1000mL), so there are 0.25L⋅3.0mol/L=0.75mol of NaOH. The molar mass of NaOH is 40.0 g/mol, so there are 0.75mol⋅40.0g/mol=30g of NaOH, 30.

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5.3 moles of H3PO4 form from 8.0 moles of H2O.

What is Moles?

Moles (mol) is a unit of measurement used in chemistry to express amounts of a chemical substance. One mole of a substance is defined as the amount of that substance that contains as many elementary entities (such as atoms, molecules, or ions) as there are atoms in 12 grams of carbon-12, which is Avogadro's number (6.022 × 10²³) of particles.

According to the balanced chemical equation, 1 mol of P4010 reacts with 6 mol of H2O to produce 4 mol of H3PO4. Therefore, we can set up a proportion:

6 mol H2O/1 mol P4010 = 4 mol H3PO4/x mol H2O

Solving for x, we get:

x = (8.0 mol H2O * 4 mol H3PO4) / 6 mol H2O

x = 5.3 mol H3PO4

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Answer:

where is the other temperature? so i can help you

A double replacement is Na2SO4 (aq) + BaCl2 BaSO4 (s) + 2 NaCl (aq) + 2 NaCl (aq). The reaction Na2SO4 + BaCl2 is endothermic. When barium chloride (BaCl2) and sodium sulphate (Na2SO4) combine, sodium chloride and barium sulphate are formed.

When Sodium sulphate(Na 2 SO 4) interacts with Barium chloride solution (), a white precipitate of Barium sulphate() and Sodium chloride is generated.

When barium chloride is introduced to dilute sulphuric acid, a white precipitate of barium sulphate forms as a result of barium displacement from its chloride, as seen below: BaCl2 + H2SO4 BaSO4 + 2HCl.

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Here is your answer. Please mark me as Brainliest if possible! :) You can redraw this.

Magnesium oxide turns a white powder as a result. Magnesium creates by transferring two electrons oxygen atoms. This reaction is exothermic. Magnesium + oxygen → magnesium oxide. 2Mg + O2 → 2MgO.

An illustration of a combination reaction is the burning of magnesium ribbon to produce magnesium oxide. One chemical splits into two compounds, one with a high oxidation state and the other with a low oxidation state, in a disproportionation reaction.

The evolution of light and heat causes an exothermic chemical reaction that results in fire. Three essential components—oxygen, heat, and fuel—must all be present for such a fire to start. The kind of reaction that results in flames is referred to as a combustion reaction in chemistry.

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The mass of carbon dioxide produced from the complete combustion of 8.40x10^-3 g of methane is 0.023 g.

Mass can be defined as the measure of the amount of matter in a body.

The balanced chemical equation for the complete combustion of methane (CH4) is:

CH4 + 2O2 → CO2 + 2H2O

This equation tells us that one mole of methane reacts with two moles of oxygen gas (O2) to produce one mole of carbon dioxide (CO2) and two moles of water (H2O).

We can use the molar mass of methane and the balanced equation to determine the amount of carbon dioxide produced from the given mass of methane.

First, we need to convert the mass of methane to moles:

moles of CH4 = mass / molar mass = 8.40x10^-3 g / 16.04 g/mol = 5.239x10^-4 moles

Next, we can use the balanced equation to find the number of moles of CO2 produced:

1 mole of CH4 produces 1 mole of CO2

So, 5.239x10^-4 moles of CH4 will produce 5.239x10^-4 moles of CO2.

Finally, we can use the molar mass of carbon dioxide to convert moles to grams:

mass of CO2 = moles of CO2 × molar mass of CO2

mass of CO2 = 5.239x10^-4 moles × 44.01 g/mol = 0.023 g

Therefore, the mass of carbon dioxide produced from the complete combustion of 8.40x10^-3 g of methane is 0.023 g.

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The bleach solution has a molarity of 0.0637 M.

Sodium hypochlorite is an inorganic chemical compound with the formula NaOCl (or NaClO), consisting of a sodium cation (Na+) and a hypochlorite anion (OCl or ClO). It is usually referred to in diluted solutions as (chlorine) bleach. It can also be thought of as hypochlorous acid's sodium salt.

Converting the mass of bleach (NaOCl) to moles is the first step.

moles of NaOCl = mass of NaOCl / molar mass of NaOCl

The molar mass of NaOCl is approximately 74.44 g/mol (22.99 g/mol for Na, 15.99 g/mol for O, and 35.45 g/mol for Cl).

moles of NaOCl = 9.50 g / 74.44 g/mol

moles of NaOCl = 0.1274 mol

Next, we may determine the molarity (M) of the bleach solution using the notion of molarity:

Molarity = moles of solute / liters of solution

The solution's volume is supplied to us in millilitres, so we must convert it to litres:

2,000 ml = 2,000 / 1,000 = 2.00 L

Molarity = 0.1274 mol / 2.00 L

Molarity = 0.0637 M

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The tests that can be used to determine the kinds of solids that have been listed are shown below.

Here are some tests that can be used to show that a solid is:

Ionic (NaCl):

Solubility test: NaCl is highly soluble in water, and a high degree of solubility can confirm the ionic nature of NaCl.

Conductivity test: In its molten or dissolved state, NaCl conducts electricity due to the presence of charged ions.

Metallic (Ca):

Conductivity test: Metals such as Ca conduct electricity due to the presence of free electrons in their crystal structure.

Ductility and malleability test: Metals are ductile and malleable, and can be easily deformed under pressure.

Covalent Network (Quartz, SiO2):

Hardness test: Covalent network solids such as quartz are extremely hard due to the strong covalent bonds between atoms.

Melting point test: Covalent network solids often have high melting and boiling points due to the strong intermolecular forces between atoms.

Polar Molecular (sugar, C6H12O6):

Solubility test: Polar molecules such as sugar are soluble in polar solvents such as water but insoluble in nonpolar solvents.

Melting and boiling point test: Polar molecular solids have lower melting and boiling points compared to ionic or covalent network solids due to weaker intermolecular forces.

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The mass of water, H₂O produced by the reaction of 1.06 grams of oxygen gas, O₂ is 0.72 grams

The mass of water, H₂O produced by the reaction of 1.06 grams of oxygen gas, O₂ can be obtained as shown below:

The balanced equation for the reaction is given below

4NH₃ + 5O₂ -> 4NO + 6H₂O

From the balanced equation above,

160 g of oxygen gas, O₂ reacted to produce 108 g of water, H₂O

Therefore,

1.06 g of oxygen gas, O₂ will react to produce = (1.06 × 108) / 160 = 0.72 g of water, H₂O

Thus, the mass of water, H₂O produced from the reaction is 0.72 g

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The compound would have six hydrogen bonds.

It has 3 H bond acceptors. It can form six H bonds with an identical molecule. It can form three hydrogen bonds with water.

Hydrogen bonds are a type of intermolecular force that occurs between a hydrogen atom bonded to an electronegative atom (such as nitrogen, oxygen, or fluorine) and a nearby electronegative atom on another molecule.

The hydrogen bond is a weak electrostatic attraction between the partially positive hydrogen and the partially negative atom, which is typically a lone pair of electrons on the other molecule.

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Answer:

To make an 800 mL solution of 3.0 M glucose (C6H12O6), you would need 2.4 moles of glucose.

Here’s the work: Molarity (M) = moles of solute / liters of solution Rearranging the equation to solve for moles of solute: moles of solute = Molarity (M) * liters of solution Since you have 800 mL or 0.8 L of a 3.0 M glucose solution: moles of glucose = 3.0 M * 0.8 L = 2.4 moles.

Answer is closest to option (a) 2850 g. The mole is a fundamental concept in chemistry and is used extensively in calculations involving chemical reactions and stoichiometry.

What is Mole?

The mole is used to convert between the mass of a substance and the number of particles it contains. For example, the molar mass of a substance (the mass of one mole of that substance) can be used to convert the mass of a sample to the number of moles of that substance present.

The balanced chemical equation for the reaction is:

P4O10(s) + 6H2O(l) → 4H3PO4(aq)

From the equation, we can see that for every 6 moles of water that react, 4 moles of H3PO4 are produced.

So, to calculate the moles of H3PO4 produced, we first need to calculate the moles of water that react. The question states that 43.6 moles of water react, so we can use this value to calculate the moles of H3PO4 produced:

moles of H3PO4 = (4/6) x 43.6 = 29.07 moles

Finally, we can use the molar mass of H3PO4 to convert moles to grams:

grams of H3PO4 = moles of H3PO4 x molar mass of H3PO4

= 29.07 moles x 98 g/mol

= 2848.86 g

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If the density of mercury is 13.6 g/mL, the volume of a 155-gram sample of mercury is 11.397 mL.

It follows that:

Mercury has a density of 13.6 g/mL.

155 grammes make to the mercury's weight.

The fact is,

A three-dimensional space enclosed by an object or thing is referred to as its volume.

Mass times volume equals density.

13.6 = Volume 155

quantity = 155/13.6

11.397 mL is the capacity.

As a result, assuming mercury has a density of 13.6 g/mL, a 155-gram sample of mercury has a volume of 11.397 mL.

The complete question is:

The density of mercury is 13.6 g/mL. What is the volume of a 155-gram sample of mercury?

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a. The rate law rate=k[NO2]^2 indicates that the reaction is second order with respect to NO2.

b. The rate law rate=k indicates that the reaction is zero order with respect to the reactant(s).

c. The rate law rate=k[H2][Br2]^1/2 indicates that the reaction is first order with respect to H2 and half-order with respect to Br2. Therefore, the overall order of the reaction is 1 + 1/2 = 3/2 order.

d. The rate law rate=k[NO]^2[O2] indicates that the reaction is third order overall. The reaction is second order with respect to NO and first order with respect to O2.

The term "rate law" is commonly used to refer to the integrated rate law. K in a rate law is the rate constant, a value specific to each reaction that determines the rate of reaction. Orders in a rate law describe the dependency of the reaction rate on the concentration of each reactant, with each reactant having its own order. The overall reaction order is the sum of the individual orders, which can be determined through experiments.

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The car took 3 seconds to accelerate from 15 m/s to 30 m/s with an acceleration of 5 m/s^2.

We can use the following kinematic equation to solve this problem:

v = u + at

Where

Given:

u = 15 m/s (initial velocity)

v = 30 m/s (final velocity)

a = 5 m/s^2 (acceleration)

Substituting the given values into the equation, we get:

30 m/s = 15 m/s + 5 m/s^2 × t

Simplifying and solving for t, we get:

5 m/s^2 × t = 15 m/s

t = 15 m/s ÷ 5 m/s^2 = 3 seconds

Therefore, the car took 3 seconds to accelerate from 15 m/s to 30 m/s with an acceleration of 5 m/s^2.

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Answer: 69.9 g  

Explanation:

The degree of association of AlCl3 into Al2Cl6 is 0.663. The degree of association of AlCl3 into Al2Cl6 can be determined using the ideal gas law and the van't Hoff factor.

Firstly, we need to calculate the number of moles of AlCl3 present in the vessel using the formula n = m/M, where m is the mass of AlCl3 and M is the molar mass of AlCl3.

n = 10.32g / 133.34 g/mol = 0.0774 mol

Next, we can use the ideal gas law equation PV = nRT to calculate the number of moles of particles in the gas phase. Rearranging this equation, we get:

n = PV/RT

where P is the pressure, V is the volume, R is the gas constant and T is the temperature in Kelvin.

n = (1.7 x 10 N/m²) x 1 dm³ / (8.31 J/mol/K x 353 K) = 7.55 x 10⁻⁴ mol

The van't Hoff factor (i) is the ratio of the actual number of particles in solution to the number of formula units dissolved. For a completely dissociated compound, the van't Hoff factor is equal to the number of ions produced. In the case of AlCl3, it undergoes a degree of association to form Al2Cl6, so the van't Hoff factor is less than 1.

We can now use the formula i = 1 + (α - 1)β, where α is the degree of association and β is the number of particles in solution per formula unit. For AlCl3, β = 4 (AlCl3 contains one Al and three Cl atoms), and assuming a degree of association of x, we get:

i = 1 + (x - 1) x 4 = 4x - 3

Substituting the values for n and i into the equation n = iC, where C is the concentration in mol/dm³, we get:

7.55 x 10^-4 mol = (4x - 3) C

Solving for x, we get:

x = 0.663

Therefore, the degree of association of AlCl3 into Al2Cl6 is 0.663.

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The number of particles in the gas is [tex]4.72 * 10^{24}[/tex], the volume of the gas at 4 atm is 40 L, and the volume of the gas at 300 K is 30 L.

Avogadro's Law: Equal volumes of gases at the same temperature and pressure contain equal numbers of particles (molecules or atoms).

Boyle's Law: For a fixed amount of gas at a constant temperature, the pressure and volume are inversely proportional to each other.

Charles's Law: For a fixed amount of gas at a constant pressure, the volume and temperature are directly proportional to each other.

PV = nRT is the formula for the ideal gas law,

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

Mass of gas (m) = 4 g

Temperature (T) = 200 K

Pressure (P) = 8 atm

Volume (V) = 20 L

First, we can use the ideal gas law to calculate the number of moles of gas:

n = PV/RT

n = (8 atm * 20 L) / (0.0821 L.atm/mol.K * 200 K)

n = 7.85 moles

Next, we can use Avogadro's Law to find the number of particles (molecules or atoms):

1 mole of gas = [tex]6.02 * 10^23[/tex] particles

7.85 moles of gas =[tex]7.85 * 6.02 * 10^23[/tex]particles

= [tex]4.72 * 10^24[/tex] particles

We can also use Boyle's Law and Charles's Law to find the volume of the gas at different conditions:

Boyle's Law:

[tex]P_1V_1 = P_2V_2[/tex]

If we keep the temperature constant at 200 K, we can use this relationship to find the volume of the gas at a different pressure. Let's say we want to know the volume of the gas at 4 atm:

[tex]P_1[/tex] = 8 atm

[tex]V_1[/tex] = 20 L

[tex]P_2[/tex] = 4 atm

[tex]V_2[/tex]= ?

[tex]P_1V_1 = P_2V_2[/tex]

8 atm x 20 L = 4 atm x [tex]V_2[/tex]

[tex]V_2[/tex] = (8 atm x 20 L) / 4 atm

[tex]V_2[/tex] = 40 L

Charles's Law:

[tex]V1/T1 = V2/T2[/tex]

If we keep the pressure constant at 8 atm, we can use this relationship to find the volume of the gas at a different temperature.

Let's say we want to know the volume of the gas at 300 K:

[tex]V_1[/tex] = 20 L

[tex]T_1[/tex]= 200 K

[tex]V_2[/tex] = ?

[tex]T_2[/tex] = 300 K

[tex]V_1/T_1 = V_2/T_2[/tex]

20 L / 200 K = [tex]V_2[/tex] / 300 K

[tex]V_2[/tex] = (20 L / 200 K) x 300 K

[tex]V_2[/tex] = 30 L

Therefore, the number of particles in the gas is [tex]4.72 * 10^{24}[/tex], the volume of the gas at 4 atm is 40 L, and the volume of the gas at 300 K is 30 L.

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[tex]Fe +2 HCl[/tex] yields [tex]FeCl_2[/tex] and [tex]H_2[/tex]. One atom of [tex]Fe[/tex] combines with two compounds of [tex]HCl[/tex] to create 1 molecule of [tex]FeCl_2[/tex]  or one molecule of [tex]H_2[/tex], as shown by the equation's balanced form.    [tex]2Fe + 2HCl = 2FeCl_2 + H_2[/tex]

A mathematical statement known as an equation is created when two expressions are joined by the equal sign. An example is [tex]3x - 5[/tex] 16 in mathematics. By resolving this equation, we may find that the variable x has a value of 7.

[tex]Fe^ +2[/tex]  [tex]HCl[/tex] produces [tex]H_2[/tex] and  [tex]FeCl2.[/tex] According to the equation's balanced version, one atom of Fe reacts with two [tex]HCl[/tex] molecules to make one molecule of [tex]FeCl_2[/tex] or one molecule of  [tex]H_2[/tex].

Therefore, [tex]2Fe + 2HCl = 2FeCl_2 + H_2[/tex] one atom of Fe reacts with two [tex]HCl[/tex] molecules to make one molecule of [tex]FeCl_2[/tex] or one molecule of  [tex]H_2[/tex].

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The total enzyme concentration [Et] is 6 nM.

Enzyme concentration is the amount of an enzyme present in a given solution. The concentration of enzymes can have an effect on the rate of reaction. If the concentration of enzymes is higher, the rate of reaction will be faster, and if the concentration of enzymes is lower, the rate of reaction will be slower.Enzyme concentration is important because it can affect the outcome of a reaction, and therefore, it must be carefully monitored.

The total enzyme concentration [Et] can be calculated using the Michaelis-Menten equation, which states that[tex]Vo= [Et] * kcat * (\frac{[S]}{Km} + [S])[/tex]

Plugging in the given values, we get:

[tex]480 nM/min = [Et] * 20 min^{-1}* (\frac{6mM}{4uM} + 6mM)[/tex]

Solving for [Et], we get:

[Et] = 6 nM

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Answer:

Nucular

Explanation:

When one atom splits into 2, it's nucular

The chlorine radicals can also react with each other to form chlorine molecules, which terminates the chain reaction.

(i) The monochlorinated products resulting from the reaction of 2-methylpentane are:

1-chloro-2-methylpentane

2-chloro-2-methylpentane

3-chloro-2-methylpentane

(ii) The major product in this reaction is 2-chloro-2-methylpentane.

(iii) The step-wise mechanism for the radical halogenation of 2-chloro-2-methylpentane are:

1. Initiation :- This step involves the homolytic cleavage of the chlorine molecule to form two chlorine radicals.

[tex]Cl^ 2[/tex]→ [tex]2Cl[/tex]·

2.Propagation:-  [tex]Cl[/tex]· + 2-methylpentane → [tex]HCl[/tex] + 2-methylpentyl•

  2-methylpentyl• +[tex]Cl^ 2[/tex] → 2-chloro-2-methylpentyl• + [tex]Cl[/tex]·

The 2-methylpentane molecule reacts with the chlorine radical to form a 2-methylpentyl radical and hydrogen chloride. The 2-methylpentyl radical then reacts with another chlorine molecule to form the 2-chloro-2-methylpentyl radical and another chlorine radical.

3.Termination:- 2-methylpentyl• + [tex]Cl[/tex]· → 2-chloro-2-methylpentane

2-methylpentyl• + 2-methylpentyl• → 2,2-dimethylpentane

[tex]Cl[/tex]· + [tex]Cl[/tex]· → [tex]Cl^ 2[/tex]

The 2-chloro-2-methylpentyl radical reacts with a chlorine radical to form the major product, 2-chloro-2-methylpentane. The 2-methylpentyl radical also reacts with another 2-methylpentyl radical to form 2,2-dimethylpentane.

Finally, the chlorine radicals can also react with each other to form chlorine molecules, which terminates the chain reaction.

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Because sodium is such a highly reactive metal, it interacts with water quickly to produce sodium hydroxide and hydrogen gas. The correct chemical formula is: H2O + Na(s) = NaOH (aq) + H2 (g)

Hydrochloric acid and lithium oxide react, neutralising the acid. Lithium chloride and water are the results of the process.

A larger surface area is exposed to the water as the molten metal flows across it. Moreover, among all alkali metals, lithium has the largest hydrated radius. This reduces the ionic mobility, which causes the molten metal to move more slowly.

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The balanced chemical equation for the reaction between H₂SO₂ and KOH is:

H₂SO₂ + 2KOH → K₂SO₂ + 2H₂O

From the equation, we can see that 1 mole of H₂SO₂ reacts with 2 moles of KOH.

Given that 300 mL of 0.5 M KOH are required to neutralize 15.0 mL of H₂SO₂, we can calculate the number of moles of KOH used:

moles of KOH = Molarity × Volume (in liters) = 0.5 × 0.3 = 0.15

Since 2 moles of KOH react with 1 mole of H₂SO₂, the number of moles of H₂SO₂ in the 15.0 mL sample can be calculated as:

moles of H₂SO₂ = 0.15/2 = 0.075

The molar concentration of H₂SO₂ can be calculated as:

Molarity = moles/volume (in liters) = 0.075/(15/1000) = 5 M

Therefore, the molar concentration of H₂SO₂ is 5 M, which is magenta in the given color options.

Answer:

The balanced chemical equation for the reaction between sulfuric acid (H₂SO₄) and potassium hydroxide (KOH) is:

H₂SO₄ + 2KOH → K₂SO₄ + 2H₂O

From the balanced equation, we can see that the stoichiometry of the reaction is 1:2, which means that 1 mole of H₂SO₄ reacts with 2 moles of KOH.

Given that 300 mL of 0.5 M KOH is required to completely neutralize a 15.0 mL sample of H₂SO₄, we can use the following equation to determine the molarity of H₂SO₄:

Molarity of H₂SO₄ x Volume of H₂SO₄ = 2 x Molarity of KOH x Volume of KOH

Molarity of H₂SO₄ = (2 x Molarity of KOH x Volume of KOH) / Volume of H₂SO₄

Molarity of H₂SO₄ = (2 x 0.5 M x 0.300 L) / 0.015 L = 20 M

Therefore, the molar concentration of the initial H₂SO₄ solution was 20 M, which corresponds to option (yellow green).