The specific heat of gold is 0.129 J/g C. A king gets sold a gold crown but he's unsure if it's pure gold. He takes the crown which weighs 1,130 grams, heats it to 98.8 C, and then places it in 1.34 L of water with a starting point of 25.83 C. The final temperature of the water is 27.84 C. What is the specific heat of the crown and is it pure gold?

We see here that the article is actually talking about: B. Dr. Dituri's Project Neptune 100.

A piece of writing known as an article is typically printed in a newspaper, magazine, or journal. It may address a variety of subjects, such as news, features, essays, research findings, and reviews.

We can see here that in the article, being referred to in the question is known as "A Chat With the Scientist Living Underwater for 100 Days,".

From the article, it is very clear that it refers to Dr. Dituri's Project Neptune 100. Retired Navy officer, Joseph Dituri is seeking to break the current record for longest period of time spent submerged.

Note: I can't post the article here. But I have provided the title of the article above.

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The precipitation of an ionic substance from solution occurs when the ionic product exceeds the value of its solubility product at that temperature. Here the moles of Na₂S₂O₃ needed is

The solubility product of a sparingly soluble salt is defined as the product of the molar concentrations of its ions in a saturated solution of it at a given temperature.

Here the concentration of Ag⁺ ions = √Ksp = √3.3 × 10⁻¹³ = 1.81 × 10⁻¹³.

Moles of Ag⁺ ions: (1.82 x 10⁻¹³ M) x 1.0 L = 1.82 x 10⁻¹³  mol Ag⁺

Use the stoichiometry of the reaction to find the moles of Na₂S₂O₃ needed: 1 mol Na₂S₂O₃ / 2 mol Ag⁺ = 0.5 mol Na₂S₂O₃/mol Ag⁺

Moles of Na₂S₂O₃ required: 0.5 mol Na₂S₂O₃/mol Ag⁺ x 1.82 x 10⁻¹³ mol Ag⁺ = 9.1 x 10⁻¹⁴ mol Na₂S₂O₃

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a) The amount of N₂O₅ is lowered to 2.5 g during the course of around 4.41 × 10⁴  seconds or 12.25 hours.

b) 9.71 L of O₂ are generated at 745 mmHg and 45 °C.

a) To solve for the time required for the quantity of N₂O₅ to be reduced to 2.5 g, use the first-order integrated rate law:

ln[N₂O₅]t/[N₂O₅]0 = -kt

where [N₂O₅]t = concentration of N₂O₅ at time t, [N₂O₅]0 = initial concentration of N₂O₅, k = rate constant, and t = time.

Find the initial concentration of N₂O₅:

n(N₂O₅) = m/M = 80.0 g / 108.01 g/mol = 0.7413 mol

[N₂O₅]0 = n/V = 0.7413 mol / 0.153 L = 4.846 M

where M = molar mass of N₂O₅ and V = volume of the solution.

Substituting the given values into the equation:

ln([N₂O₅]t / 4.846 M) = -6.2×10⁻⁴ s⁻¹ × t

When the quantity of N₂O₅ is reduced to 2.5 g, the concentration is:

n(N₂O₅) = m/M = 2.5 g / 108.01 g/mol = 0.02314 mol

[N₂O₅]t = n/V = 0.02314 mol / 0.153 L = 0.151 M

Substituting this concentration into the equation and solving for t:

ln(0.151 M / 4.846 M) = -6.2×10⁻⁴ s⁻¹ × t

t = 4.41 × 10⁴ s

Therefore, it takes approximately 4.41 × 10⁴ seconds or 12.25 hours for the quantity of N₂O₅ to be reduced to 2.5 g.

b) The balanced equation for the reaction shows that 1 mole of N₂O₅ produces 1/2 mole of O₂:

N₂O₅ → N₂O₄ + 1/2 O2

Therefore, the number of moles of O₂ produced can be calculated using the stoichiometry:

n(O₂) = 1/2 × n(N₂O₅) = 1/2 × 0.7413 mol = 0.3707 mol

The ideal gas law can be used to calculate the volume of O₂ produced at 745 mmHg and 45°C:

PV = nRT

where P = pressure, V = volume, n = number of moles, R = gas constant, and T = temperature in Kelvin.

Convert the pressure to atm and the temperature to Kelvin:

P = 745 mmHg / 760 mmHg/atm = 0.980 atm

T = 45°C + 273.15 = 318.15 K

Substituting the values and solving for V:

V = nRT/P = (0.3707 mol) × (0.08206 L·atm/mol·K) × (318.15 K) / (0.980 atm) = 9.71 L

Therefore, the volume of O₂ produced at 745 mmHg and 45°C is 9.71 L.

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The surface area of the rectangular prism is 0.034 square meters.

For a rectangular prism with length l, width w, and height h, the surface area is:

Surface area = 2lw + 2lh + 2wh

Substituting the given values, we get:

Surface area = 2(10 cm x 5 cm) + 2(10 cm x 8 cm) + 2(5 cm x 8 cm)

Surface area = 100 cm² + 160 cm² + 80 cm² = 340 cm²

We can use dimensional analysis. So the conversion factor is:

1 m² / 10,000 cm²

Multiplying the surface area by this conversion factor, we get:

Surface area = 340 cm² x (1 m² / 10,000 cm²)

Surface area = 0.034 m²

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--The complete Question is, What is the surface area of a rectangular prism that has a length of 10 cm, a width of 5 cm, and a height of 8 cm? Use dimensional analysis to convert the answer to square meters--

Answer:

Explanation:

According to the Law of Conservation of Mass, matter cannot be created or destroyed in a chemical reaction. Therefore, the mass of the reactants must be equal to the mass of the products.

If 15 grams of reactant went into the reaction, then the mass of the products formed must also be 15 grams. This assumes that the reaction is complete and no reactants are left unreacted.

It is important to note that this applies to closed systems where there is no loss or gain of mass. In real-world situations, some mass may be lost due to factors such as evaporation or incomplete reactions, which can affect the accuracy of the calculations.

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The average speed of a gas molecule is proportional to the square root of its temperature and inversely proportional to the square root of its molar mass. Therefore, we can use the following equation to find the average speed of a CO2 molecule at the same temperature:

v2/v1 = sqrt(M1/M2)

where v1 and v2 are the average speeds of the oxygen and CO2 molecules, respectively, M1 and M2 are the molar masses of oxygen and CO2, respectively.

The molar mass of oxygen (O2) is 32 g/mol, and the molar mass of CO2 is 44 g/mol.

We are given that the average speed of an oxygen molecule is 4.37 × 10^4 cm/s at 25°C. We can convert the temperature to Kelvin by adding 273.15 to get:

T = 25°C + 273.15 = 298.15 K

Now we can solve for v2:

v2 = v1 * sqrt(M1/M2)

v2 = 4.37 × 10^4 cm/s * sqrt(32 g/mol / 44 g/mol)

v2 = 3.67 × 10^4 cm/s

Therefore, the average speed of a CO2 molecule at the same temperature is 3.67 × 10^4 cm/s.

The volume of N2 produced each day is approximately 24.56 L.

First, let's find the number of moles of NO3- that flow into the swamp each day:

NO3- molar mass = 14.01 (N) + 3 * 16.00 (O) = 62.01 g/mol

135 g / 62.01 g/mol ≈ 2.177 moles of NO3-

In the denitrification process, NO3- is reduced to N2 gas. The balanced equation for denitrification is:

2NO3- → N2 + 3O2

From the stoichiometry of the reaction, we can see that 2 moles of NO3- produce 1 mole of N2. Therefore, the moles of N2 produced each day can be calculated as follows:

moles of N2 = 2.177 moles of NO3- / 2 ≈ 1.0885 moles of N2

Now we can use the ideal gas law equation to find the volume of N2 produced:

PV = nRT

where:

P = Pressure (1.00 atm)

V = Volume (in Liters)

n = Moles of N2 (1.0885 moles)

R = Ideal gas constant (0.0821 Latm/molK)

T = Temperature (17.0°C or 290.15 K)

Solving for the volume of N2:

V = nRT / P

V = (1.0885 moles) * (0.0821 Latm/molK) * (290.15 K) / (1.00 atm)

V ≈ 24.56 L

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[tex]FeCl_3[/tex] is added to ensure all reducing agent is oxidized, indicating endpoint in dichromate titration.

In a dichromate titration,   [tex]FeCl_3[/tex] is frequently added to the example arrangement as a sign of the endpoint. The expansion of [tex]FeCl_3[/tex] to the example arrangement assists with guaranteeing that the lessening specialist has been all oxidized by the potassium dichromate ([tex]K_2Cr_2O_7[/tex] ) arrangement.

[tex]FeCl_3[/tex] responds with any overabundance[tex]K_2Cr_2O_7[/tex]  in the answer for structure a red-earthy colored encourage of[tex]Fe(OH)_3[/tex] , demonstrating that the lessening specialist has been all oxidized. This response is known as a "back-titration" since overabundance[tex]K_2Cr_2O_7[/tex]   is added to the arrangement, trailed by the option of [tex]FeCl_3[/tex] to decide how much unreacted [tex]K_2Cr_2O_7[/tex] .

The response somewhere in the range of [tex]FeCl_3[/tex] and [tex]K_2Cr_2O_7[/tex] can be addressed as:

[tex]6FeCl_3 + K_2Cr_2O_7 + 7H_2SO_4 → 3Fe_2(SO_4)_3 + Cr_2(SO_4)_3 + K_2SO_4 + 7H_2O + 3Cl_2[/tex]

The [tex]FeCl_3[/tex] goes about as a pointer in this response since it responds with the overabundance [tex]K_2Cr_2O_7[/tex] until the decreasing specialist has been all oxidized. As of now, the red-earthy colored encourage of [tex]Fe(OH)_3[/tex]  structures, showing that the endpoint has been reached.

Without the expansion of [tex]FeCl_3[/tex], it would be challenging to precisely decide the endpoint of the titration. The expansion of [tex]FeCl_3[/tex] is important to guarantee that the lessening specialist has been all oxidized and that the endpoint has been reached, considering a more exact assurance of the grouping of the diminishing specialist in the example arrangement.

In outline, the expansion of [tex]FeCl_3[/tex] to the example arrangement in a dichromate titration is significant in light of the fact that it assists with guaranteeing that the decreasing specialist has been all oxidized, considering a more precise assurance of its focus.

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The complete question is -

What is the reason for a dichromate titration, and how does [tex]FeCl_3[/tex]support deciding the endpoint of the titration? Might you at any point give the compound condition to the response somewhere in the range of [tex]FeCl_3[/tex] and [tex]K_2Cr_2O_7[/tex] and make sense of why [tex]FeCl_3[/tex] goes about as a marker in this response?

The solubility of NH₃ in water at 90°C is approximately 0.03 g per 100 g of water.

The solubility can be determined from a solubility table or by using the appropriate equilibrium constant.

According to a solubility table, the solubility of ammonia in water at 90°C is approximately 88 g per 100 g of water.

Alternatively, the equilibrium constant for the dissolution of ammonia in water at 90°C can be used to calculate the solubility.

The equilibrium constant (K) for the reaction:

NH3 (g) + H2O (l) ⇌ NH4+ (aq) + OH- (aq)

is approximately 1.76 x 10⁻⁵ at 90°C.

Using the equilibrium constant expression:

K = [NH4+][OH-]/[NH3][H2O]

Assuming that the concentration of water remains constant at 100 g per 100 g of solution, and that the concentration of NH4+ and OH- are negligible compared to that of NH3, the solubility of NH3 can be calculated as:

[NH3] = K[H2O] = 1.76 x 10⁻⁵ x 100 = 1.76 x 10⁻³ mol/L

Converting to grams per 100 g of water:

1.76 x 10⁻³ mol/L x 17.03 g/mol = 0.03 g/100 g of water

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The complete question is below:

determine the solubility of NH₃ in water at 90° C​

Final temperature: 677.4K. Work done: -7026J.

Heat exchanged: 0J. Change in internal energy: -7026J.

(i) For an adiabatic process, T1(V1)^γ-1 = T2(V2)^γ-1.

When we substitute the values (γ=1.4, T1=300K, V1=6dm³, V2=2dm³), we get T2 = 677.4K.

(ii) w = -(P1V1 - P2V2)/(γ-1) = -(nRT1 - nRT2)/(γ-1) = -5 * 8.314 * (677.4 - 300) / 0.4 = -7026J.

For adiabatic, q = 0. ΔE = q + w = -7026J (since q=0).

Final temperature: 677.4K. Work done: -7026J.

Heat exchanged: 0J. Change in internal energy: -7026J.

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The feather is the least thick of the bunch. This is due to the fact that density is defined as mass per unit volume.

A feather has a relatively low mass compared to its volume, due to its porous and lightweight nature. Marble, coin, and phone all have substantially higher densities than a feather since they are constructed of denser materials such as stone, metal, and plastic/electronics.

As a result, when the density of these things is compared, the feather is the least dense.

Because it has a significantly smaller mass than the other objects listed, the feather would be the least dense. Because density is defined as mass per unit volume, an object with a lower mass and the same or greater volume has a lower density.

The stone, coin, and phone all have greater masses and thus higher densities than the feather. However, because density varies based on the exact material used, the relative densities of these things may change if they are made of different materials.

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The given answer statement  "there is no aluminum left" and " limiting reactants is aluminum" are correct.

In the analysis of Trial 2, it was found that there was no aluminum left after the reaction had taken place. This indicates that all of the aluminum had reacted with the copper (II) chloride and that it was the limiting reactant in the reaction.

To confirm this, the mass of each reactant was converted to moles using their respective molar masses. It was found that the aluminum had a smaller number of moles than the copper (II) chloride, indicating that it would be used up first and thus be the limiting reactant.

Therefore, the limiting reactant in Trial 2 was aluminum.

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Question #3: 0.8 g of NaHCO3 mass NaCI weight: 0.4 g 0.8 g/84 g/mol, or 0.0095 moles, of NaHCO3 0.4 g/58.5 g/mol = 0.0068 moles of NaCI are the moles.

The reaction's mole to mole ratio and the ratio in the balanced equation (1:1) are in agreement. The highest quantity of NaCI that may be produced from this reaction is 0.0095 moles since NaHCO3 is the limiting reactant.

The theoretical yield of NaCI is 0.0095 moles, which is question #6. The finished product weighs 0.4 g. The percent yield is 0.4 g/0.0095 moles times 100, which is 42.1%.

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The standard cell potential is found as +1.95 V and is a  spontaneous  reaction.

The standard cell potential (E°cell) of an electrochemical cell is given by the difference between the standard reduction potentials of the two half-cells involved.

E°cell = E°reduction (cathode) - E°reduction (anode)

The half-reactions given are:

Pb4+ + 2e− → Pb2+ (reduction)

Co3+ + e− → Co2+ (reduction)

The standard reduction potentials for these half-reactions are:

E°reduction(Pb4+/Pb2+) = -0.13 V

E°reduction(Co3+/Co2+) = +1.82 V

We then calculate as:

E°cell = E°reduction (Co3+/Co2+) - E°reduction (Pb4+/Pb2+)

E°cell = (+1.82 V) - (-0.13 V)

E°cell = +1.95 V

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Answer:

Glyceraldehyde is a simple sugar with three carbon atoms attached to hydroxyl and hydrogen or carbonyl groups. The first carbon atom has four different groups, including an aldehyde group, which makes it asymmetric. This results in two stereoisomers, D-glyceraldehyde and L-glyceraldehyde, that are mirror images of each other and have opposite optical activities.

(a) To calculate the mass of sulfuric acid in the truck, we can multiply the volume of sulfuric acid by its density. Given that the truck carries 34,000 liters of sulfuric acid and the density of sulfuric acid is 1.84 kg/L.

we can use the formula:

Mass (m) = Volume (V) × Density (D)

Plugging in the given values:

Volume (V) = 34,000 L Density (D) = 1.84 kg/L

m = 34,000 L × 1.84 kg/L

m ≈ 62,560 kg (rounded to the nearest whole number)

Therefore, the mass of sulfuric acid in the truck is approximately 62,560 kg.

(b) The amount of sulfuric acid in the truck is already given in the question as 34,000 L (volume).

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(a) To find the mass of sulfuric acid in the truck, we need to use the formula:
mass = density x volume

The volume of sulfuric acid in the truck is given as 34,000 L. The density of sulfuric acid is 1.84 kg/L. Therefore, the mass of sulfuric acid in the truck is:

mass = 1.84 kg/L x 34,000 L = 62,560 kg
So there are 62,560 kg of sulfuric acid in the truck.
(b) To find the amount of sulfuric acid in the truck, we need to use the formula:
amount = mass / molar mass
The molar mass of sulfuric acid is 98.08 g/mol. To convert the mass from kg to g, we need to multiply by 1000. Therefore, the amount of sulfuric acid in the truck is:
amount = 62,560,000 g / 98.08 g/mol = 636,816.3 mol
So there are 636,816.3 moles of sulfuric acid in the truck.

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My model is distinct from the model in the image in that it takes a more thorough and all-encompassing approach to comprehending the fundamental parts of a system.

It considers the interactions between various system elements as well as the connections between those elements and their surroundings. It also looks at how the system changes over time, and how different components interact with each other.

As a result, the system may be understood more precisely, and management choices can be made with more knowledge. In order to offer a more precise and current picture of the system, my model also integrates the most recent research and technological advancements.

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The S-P difference (sec) is the time gap between the arrival of the S-wave and the arrival of the P-wave at a seismic station. The S-P discrepancy is depicted in the figure as 20 seconds.

The amplitude (mm) of a seismic wave is the largest displacement from its resting point. The amplitude of the waves is not depicted in the image and cannot be calculated based on the information provided.

Distance (km): Using the S-P time difference and the known velocity of seismic waves, the distance from the seismic station to the earthquake epicenter may be determined. Seismic wave velocity is determined by the type of wave and the features of the Earth's interior. The velocity of P-waves in the Earth's crust, for example, is around 6 km/s. We may compute the distance to the epicenter using this value and the S-P difference of 20 seconds as follows:

Distance = Speed x Time = 6 km/h x 20 seconds = 120 kilometres

As a result, the distance between the seismic station and the earthquake epicenter is about 120 km.

The magnitude of an earthquake (M) is a measurement of the energy generated by the earthquake based on the amplitude of the seismic waves and the distance to the epicenter. Magnitude is commonly measured on a logarithmic scale, with each whole number reflecting a factor of ten increase in energy release.

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C. It is absorbed and emitted in discrete chunks.

The energy in light is carried by particles called photons, which behave both like waves and like particles. According to the theory of quantum mechanics, photons can only be absorbed or emitted in discrete amounts of energy, known as quanta. This means that the energy in light is not continuous, but rather comes in specific packets or chunks. This phenomenon is known as quantization, and it has important implications for many areas of physics, including atomic and molecular physics, as well as the study of electromagnetic radiation.

Answer: C it is absorbed and emitted in descrete chunks.

Explanation:

photons of light are emitted or absorbed as electrons change energy levels

The pH of a 0.100M NaClO solution is 1.

pH, meaning power of hydrogen, is a measure of how acidic/basic a solution is. The range goes from 0 - 14, with 7 being neutral. pHs of less than 7 indicate acidity, whereas a pH of greater than 7 indicates a base.

pH is really a measure of the relative amount of free hydrogen and hydroxyl ions in the water. It can be estimated using the following formula;

pH = - log {H+}

Where;

pH = - log {0.100}

pH = 1

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The results of the lab activity showed that the larger the mass of the sun, the more likely at least one planet will fall into the habitable zone.

The mass of the sun affects the orbits of planets in a solar system. When the mass of the sun is larger, the gravitational force between the sun and the planets is stronger, causing the planets to move at a slower pace around the sun.

Conversely, when the mass of the sun is smaller, the gravitational force is weaker, causing the planets to move at a faster pace.

Additionally, when Earth is closer to the sun, the gravitational force is stronger, causing its orbit to become faster, while a farther distance from the sun results in a slower orbit.

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The mass of the HI that is produced is  1843 g

Stoichiometry is a branch of chemistry that focuses on the quantitative relationships in chemical reactions between reactants and products.

What is the number of moles?

Number of moles of [tex]N_{2} H_{4}[/tex] = 115.7 g/32 g/mol

= 3.6 moles

Now we have that the balanced reaction equation is;

[tex]N_{2} H_{4} + 2I_{2} --- > N_{2} + 4 HI[/tex]

If 1 mole of [tex]N_{2} H_{4}[/tex] produces 4 moles of HI

3.6 moles of [tex]N_{2} H_{4}[/tex] will produce 3.6 * 4/1

= 14.4 moles of HI

Mass of HI produced = 14.4 moles * 128 g/mol

= 1843 g

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A chemical interaction between an acid and a base is known as an acid-base reaction.

Thus, These are known as acid-base theories, such as the Brnsted-Lowry acid-base theory, and they offer alternative conceptions of the reaction mechanisms and their application in solving related problems.

When examining acid-base reactions for gaseous or liquid species, or when the acid or basic character may be less obvious, their significance becomes clear.

The relative potency of the conjugated acid-base pair in the salt controls the pH of its solutions when weak acids and bases react. The resulting salt or its solution can be basic, neutral, or acidic. A strong acid and a weak base can combine to generate an acid salt.

Thus, A chemical interaction between an acid and a base is known as an acid-base reaction.

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i) The equation for the reaction between hydrochloric acid and zinc is:

[tex]Zn + 2HCl → ZnCl2 + H2[/tex]

ii) n(HCl) = C × V = 1.0M × 0.05 L = 0.05 moles

iii) The volume of gas evolved at STP is 0.544 L or 544 mL.

The concentration of hydrochloric acid is 1.0M, which means that there is 1 mole of hydrochloric acid in 1 liter (1000 cm³) of solution. The volume of the hydrochloric acid used is 50 cm³, which is 0.05 liters.

According to the stoichiometry of the reaction, each mole of hydrochloric acid produces one mole of hydrogen ions, so the number of moles of hydrogen ions in the solution is also 0.05 moles.

The volume of gas evolved can be calculated from the ideal gas law:

PV = nRT

where P is the pressure of the gas, V is the volume of the gas, n is the number of moles of the gas, R is the gas constant (0.0821 L·atm/K·mol), and T is the temperature of the gas in Kelvin. At standard temperature and pressure (STP), the pressure is 1 atm and the temperature is 273 K. The molar volume of a gas at STP is 22.4 L/mol.

From the equation for the reaction, we know that one mole of hydrogen gas is produced for every two moles of hydrochloric acid used. Therefore, the number of moles of hydrogen gas produced is:

n(H2) = 0.5 × n(HCl) = 0.5 × 0.05 moles = 0.025 moles

Using the ideal gas law, we can calculate the volume of hydrogen gas produced at STP:

V(H2) = n(H2) × RT/P = 0.025 mol × 0.0821 L·atm/K·mol × 273 K/1 atm = 0.544 L

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Answer:

Explanation:

The change in entropy of a system can be determined by comparing the entropy of the reactants to the entropy of the products. The reaction that leads to an increase in the number of moles of gas or particles will generally have a positive change in entropy.

I. 2N2(g) + O2(g) → 2N2O(g)

The reactants have 3 moles of gas, while the product also has 3 moles of gas. Therefore, there is no change in the number of moles of gas, and the change in entropy is likely to be small.

II. CaCO3(s) → CaO(s) + CO2(g)

The reactant is a solid, while the products are a solid and a gas. The formation of a gas from a solid leads to an increase in the number of moles of particles, and therefore an increase in entropy.

III. Zn(s) + 2HCl(aq) → ZnCl2(aq) + H2(g)

The reactants consist of a solid and a liquid, while the products consist of an aqueous solution and a gas. The formation of a gas leads to an increase in the number of moles of particles, and therefore an increase in entropy.

Therefore, reactions II and III have a positive change in entropyentropy

Answer:

a. Cl2 (g) + 2NaI (aq) → 2NaCl (aq) + I2 (s)

b. 2NaClO3 (s) → 2NaCl (s) + 3O2 (g)

c. 2K (s) + 2H2O (l) → 2KOH (aq) + H2 (g)

Explanation: