how many chirality centers are there in an aldohexose?

The final pressure, in atm, after 9.06 g of krypton reacts with 10.0 g of fluorine at 300 k in a 10.0-l container is 0.935 atm.

Given the mass of krypton gas = 9.06g

the mass of fluorine gas = 10g

The temperature of gas = 300K

The volume of container = 10L

Let the final pressure = P

The balanced chemical equation for the reaction of krypton with fluorine is: [tex]Kr + 2F2 -- > KrF2 + F2[/tex]

We know the Molar mass of krypton = 83.798 g/mol

We know the Molar mass of fluorine = 18.998 g/mol

Moles of krypton = 9.06 g / 83.798 g/mol = 0.108 mol

Moles of fluorine = 10.0 g / 18.998 g/mol = 0.526 mol

Then, use the ideal gas law to calculate the initial pressure:

PV = nRT

[tex]P = (0.108 mol + 0.526 mol) * 0.082 * 300 K / 10.0 L[/tex]

P = 0.935 atm

Since the reactants are completely consumed, the total number of moles of gas in the container after the reaction will remain the same as before the reaction. Therefore, the pressure of the container after the reaction will also be the same as before the reaction.

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Compound x can be identified as a ketone containing a carbonyl group,

Let's start by breaking down the reaction:

Compound x (ketone) + 2 thioacetal + acid → thioacetal (product)

Thioacetal (product) + Raney nickel → diphenylmethane

In the first step of the reaction, the ketone (compound x) reacts with two equivalents of thioacetal in the presence of an acid to form the thioacetal product.

The thioacetal product is then treated with Raney nickel in the second step to form diphenylmethane.

Based on the reaction, we can infer that the carbonyl group of a ketone is replaced by a thioacetal group (-S-CH2-) when it reacts with two equivalents of thioacetal in the presence of an acid. The resulting product then undergoes hydrogenation with Raney nickel to form diphenylmethane.

Therefore, Compound x can be identified as a ketone containing a carbonyl group, but without any other functional groups that may interfere with this reaction. Without additional information or data, it is impossible to identify the specific structure of Compound x.

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1804.7 g of water is needed achieve 4.24% mass fraction.

To make a solution with a mass fraction of 4.24 %, we need to dissolve 76.4 g of the solute in an appropriate amount of water.

To calculate the amount of water needed, use the following equation:

Mass fraction (%) = (Mass of solute / Mass of solution) x 100

Therefore, Mass of solution = (Mass of solute x 100) / Mass fraction (%)

Plugging in the given values,

we get: Mass of solution = (76.4 g x 100) / 4.24 = 1801.88 g

This means that 1804.7 g of water is needed to make a solution with a 4.24% mass fraction, using 76.4 g of the solute.

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Gas particles are constantly moving quickly and randomly. Elastic collisions occur when gas particles collide with one another and with the container walls.

According to the kinetic molecular theory, gas particle collisions are completely elastic. When two objects collide in an elastic collision, their combined kinetic energy is preserved during the collision.

According to the kinetic molecular theory, collisions between gas particles occur in perfect elastic motion and are always in motion. Boyle's and Charles's laws can both be explained by the kinetic molecular theory.

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Answer:

Change in internal energy if 20J of heat is supplied to a system and gas in system has done 50J work during a thermodynamic process , will be. +30J.

The thermo ionic equation for the reaction is:

3Mg(s) + 2Al₂(SO₄)₃(aq) → 3MgSO₄(aq) + 2Al(s)

From the given information, we can calculate the amount of heat energy released during the displacement reaction of aluminium by magnesium:

Heat energy released = mass of solution × specific heat capacity × temperature change

The mass of the solution can be calculated as follows:

mass of solution = volume of solution × density of solution

= 60 cm³ × 1.04 g/cm³

= 62.4 g

The moles of aluminium sulphate in the solution can be calculated as follows:

moles of Al₂(SO₄)₃ = molarity × volume of solution

= 2.1 mol/L × 0.06 L

= 0.126 mol

Since the reaction is 3Mg + 2Al₂(SO₄)₃ → 3MgSO₄ + 2Al, we know that 2 moles of aluminium are displaced by 3 moles of magnesium. Therefore, the moles of magnesium that reacted can be calculated as follows:

moles of Mg = (0.126 mol Al₂(SO₄)₃ ÷ 2) × (3 ÷ 2) = 0.189 mol

The molar enthalpy change can be calculated as follows:

ΔH = heat energy released ÷ moles of Mg

= (62.4 g × 4.2 J/gK × 7 K) ÷ 0.189 mol

= -583.6 kJ/mol

(note the negative sign indicating an exothermic reaction)

Apart from the temperature change, effervescence may be observed due to the production of hydrogen gas.

The thermo ionic equation for the reaction is:

3Mg(s) + 2Al₂(SO₄)₃(aq) → 3MgSO₄(aq) + 2Al(s)

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When X, which contains both lactone and acetal, is treated with the reagent H3O+, it forms two products.

These products differ in molecular mass. The products are as follows:

Product 1: The first product is a cyclic hemiacetal. The acetal and lactone are both converted to hemiacetals, which are stable under acidic conditions. The formation of hemiacetal can be depicted using the following reaction: X + H3O+→ Hemiacetal This product is of lower molecular mass than X.

Product 2: The second product is an open-chain hemiacetal. The acetal and lactone are both converted to hemiacetals, which are stable under acidic conditions. The open-chain form of hemiacetal is more stable than the cyclic form, and it is therefore preferred. The formation of hemiacetal can be depicted using the following reaction: X + H3O+→ HemiacetalThis product is of higher molecular mass than X.

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The theoretical yield of MgO for Trial 1 is 0.51 g and 0.5 g for trial 2

The first step in these kinds of situations is to write out and balance your chemical reaction.

O2 + Mg + MgO

For Trival 1 and 2, we first need to calculate the moles of magnesium. We take the difference between the mass of the crucible with Mg and the mass of the empty crucible,

which is Trial 1: 26.994g - 26.688g = 0.306

Trial 2: 26.985g - 26.681g = 0.304

We then convert these to moles by dividing by the molecular weight of Mg (24.305 g/mol), which

Trial 1  0.306/24.305 = 0.0126

Trial 2 0.304/24.305 = 0.0125

The theoretical yield would be;

Trial 1; 0.0126 (24.305 + 16) = 0.507

Trial 2; 0.0125 (24.305 + 16) = 0.504

To calculate the percent yield,

Percent Yield = (Actual Yield / Theoretical Yield) x 100%

The answer provided above is based on the full question below;

Data                                           Trial 1                   Trial 2

Mass of empty crucible with lid   26.688g             26.681g

Mass of Mg metal, crucible, and lid 26.994g              26.985g

Mass of MgO, crucible, and lid  27.188g                        27.180g

1a. Magnesium is the limiting reactant in this experiment. Calculate the theoretical yield of MgO for each trial

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The halogen family is a group of non-metallic elements located in group 17 or 7A of the periodic table. Some of the characteristics of the halogen family include:

They have a high electronegativity, meaning they tend to attract electrons towards themselves in chemical bonding.

They have a high electron affinity, meaning they tend to gain electrons in chemical reactions.

They are highly reactive and tend to form compounds with other elements, especially metals.

They exist in all three states of matter at room temperature, depending on the element. For example, fluorine and chlorine are gases, bromine is a liquid, and iodine is a solid.

They are diatomic molecules in their elemental form, meaning they exist as two atoms of the same element bonded together. For example, chlorine gas (Cl2) and fluorine gas (F2).

One characteristic that is not true of the halogen family is that they are good conductors of heat and electricity. In fact, they are poor conductors of heat and electricity, which is a common characteristic of non-metallic elements. Halogens are also not typically used as structural materials, as they tend to be brittle and have low melting and boiling points compared to metals.

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P stands for pressure and is 1.89 103 kPa. This is equivalent to 1.89 x 10310.325 x 18.65 atm.

Thus, the value of $gamma $ is 1.664 for molecular formula gas such the precious gases He, Ne, or Ar and = 1.4 for diatomic gases, etc. The number of moles is n, while R is really the gas standard. As a result, 0.7L of 5.6L of argon gas at the STP is obtained by adiabatic compression.

An molecule of something like the chlorine atom helium as known as a helium atom. Hydrogen is made up of two electrons connected either by electromagnetism toward a structure comprising two protons and either one or 2 particles, based on the isotope, bound together through a strong force.

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Hydrogen can be used in fuel cells to generate electricity, or power and heat. Today, hydrogen is most commonly used in petroleum refining and fertilizer production, while transportation and utilities are emerging markets.

The general trend in densities for periods 2 and 3 in the periodic table is an increase in density from left to right across the period.

This is due to the increase in atomic number and nuclear charge as one moves across the period. As the atomic number and nuclear charge increase, the attractive forces between the positively charged nucleus and the negatively charged electrons increase, causing the electrons to be more closely held and the atoms to be smaller in size. This results in an increase in the density of the elements in the period. The trend is not always followed consistently, and there are some exceptions, particularly in transition elements. For example, chromium and copper, which are transition metals, have densities that are lower than their neighboring elements due to their electronic configurations. In general, however, the trend is useful for predicting the properties of elements based on their positions in the periodic table. It is also helpful in identifying unknown elements based on their densities, particularly if they are in the same period as other known elements with similar densities.

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The balanced chemical equation for the reaction between butane and oxygen to form carbon dioxide and water is shown below.2 C4H10(g) + 13 O2(g) → 8 CO2(g) + 10 H2O(g)We need to calculate the theoretical yield of water formed from the reaction of 2.91 g of butane and 13.5 g of oxygen gas.

To do this, we need to determine which of the two reactants is limiting and then use stoichiometry to calculate the amount of water produced. Butane reacts with oxygen in a ratio of 2:13. Therefore, to calculate the amount of oxygen needed to react with 2.91 g of butane, we use the following calculation: moles of butane = mass / molar mass = 2.91 g / 58.12 g/mol = 0.05 mol The moles of oxygen required = 0.05 mol × (13 mol of O2 / 2 mol of butane) = 0.325 mol So, the limiting reactant is oxygen because there is less of it than required. Using the stoichiometric ratio of the balanced chemical equation, we know that 10 mol of water is produced for every 13 mol of oxygen consumed.

Therefore, the number of moles of water produced can be calculated as follows: number of moles of water = 0.325 mol × (10 mol of H2O / 13 mol of O2) = 0.25 mol The mass of water produced can be calculated using its molar mass: mass of water = number of moles × molar mass = 0.25 mol × 18.02 g/mol = 4.505 g The theoretical yield of water formed from the reaction of 2.91 g of butane and 13.5 g of oxygen gas is 4.505 g of water.

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To create one mole of H₂, 2.0 moles of Ca must be reacted with 4.0 moles of water.

From the balanced chemical equation:

Ca + 2H₂O → Ca(OH)₂ + H₂

we can see that 1 mole of Ca reacts with 2 moles of H₂O to produce 1 mole of H₂. Therefore, we need to calculate how many moles of H₂O are required to react with 2.0 moles of Ca.

If 1 mole of Ca reacts with 2 moles of H₂O, then 2.0 moles of Ca will react with:

2.0 moles Ca x (2 moles H₂O/1 mole Ca) = 4.0 moles H₂O

Therefore, 4.0 moles of H₂O are needed to react with 2.0 moles of Ca to produce 1 mole of H₂.

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The percentage abundance of 235U is 0.720%, and the percentage abundance of 238U is 99.274%, given that the percentage abundance of 234U is 0.006%. These values can be calculated by subtracting the percentage abundance of 234U from 100.

Uranium is important in nuclear energy because it is a naturally occurring radioactive element that can undergo nuclear fission, which releases a significant amount of energy. Nuclear power facilities can use this energy to produce electricity.

Uranium mining can pose a variety of environmental and health risks. The mining process can generate large amounts of waste rock and tailings that can contaminate soil and water with radioactive materials. Exposure to these materials can increase the risk of cancer and other health problems.

Additionally, the transport and storage of uranium can pose a risk of accidental release, which can have significant environmental and health impacts.

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Answer:

Fossils form in five ways: preservation of original remains, permineralization, molds and casts, replacement, and compression.

Explanation:

Rock formations with exceptional fossils are called very important for scientists to study. They allow us to see information about organisms that we may not otherwise ever know.

Fossils are formed in many different ways, but most are formed when a living organism (such as a plant or animal) dies and is quickly buried by sediment (such as mud, sand or volcanic ash). Soft tissues often decompose, leaving only the hard bones or shells behind (but in special circumstances the soft tissues of organisms can be preserved). After the organism has been buried, more sediment, volcanic ash or lava can build up over the top of the buried organism and eventually all the layers harden into rock 

The molecular formula of the compound is [tex]NH_4[/tex] ammonium.

The empirical formula is the simplest ratio of atoms of each element in a compound, expressed as a whole number. To determine the molecular formula, we need to multiply the number of atoms in the empirical formula by the molar mass of the compound.In this case, the empirical formula is [tex]NH_2[/tex], meaning that there is one nitrogen and two hydrogen atoms. The chemical has a 32 g/mol molar mass.Therefore, if we multiply the number of atoms in the empirical formula by 32 g/mol, we will get the molecular formula, which is [tex]NH_4[/tex], meaning that there are four nitrogen and eight hydrogen atoms.

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The following statements are true or false:

A- To rinse the entire inner surface of the buret, one should add water from a wash bottle while rotating the buret. - True

B- Rinsing the buret with water is always enough to clean the buret. - False

C- To clean the inner surface of the buret, one should wash it with soapy water three times. - False

D- After rinsing with water and soapy water solution, one can add the titrating solution and begin the titration. - True

E- Always rinse a buret with the titration solution three times before beginning a titration. - False

To rinse the entire inner surface of the buret, one should add water from a wash bottle while rotating the buret. After using the buret, it is essential to clean it by rinsing it thoroughly. To do this, add water to the buret with a wash bottle while rotating it. This ensures that the whole inner surface of the buret is rinsed, which eliminates any residual substances.

Rinsing the buret with water is not always enough to clean the buret. While rinsing the buret with water is a crucial step in cleaning it, it is not always sufficient. Burets must be washed with soapy water to ensure that they are clean.

To clean the inner surface of the buret, one should not wash it with soapy water three times. Rather, the buret should be washed with soapy water once. The buret should be washed with a mild soap solution and then rinsed with water.

After rinsing with water and a soapy water solution, one can add the titrating solution and begin the titration. After cleaning the buret, the next step is to fill it with the titrating solution and begin the titration process.

One should not always rinse a buret with the titration solution three times before beginning a titration. After cleaning the buret, it should be rinsed thoroughly with water and not the titration solution. The titration solution should be added only when the buret is clean and ready for use.

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Answer:

250 grams

Explanation:

so if you look at the temperature of 50 and go up from there and stop at the red line you should get 250 grams, not positive but 99% of me says yes.

In the experiment design in part I, the part that explains why the pattern changed to a constant relationship between the variables at higher values for mass of CuSO4 is the controlled variable.

The controlled variable is the variable that stays the same throughout the experiment. It is also known as a constant variable, and it is not allowed to change. This is done so that the effects of the independent variable on the dependent variable can be observed.

The other variables in the experiment are independent variables and dependent variables. The independent variable is the variable that is changed in the experiment. The dependent variable is the variable that is being measured. In the experiment, the independent variable is the mass of CuSO4. The dependent variable is the absorbance value. The controlled variable is the concentration of CuSO4, the volume of the CuSO4 solution, the type of the solution, the type of the cuvette, and the wavelength used.

By keeping the concentration, volume, solution type, cuvette type, and wavelength used constant, the effects of these variables on the absorbance value can be eliminated. Therefore, any changes in the absorbance value are only caused by the changes in the independent variable, which is the mass of CuSO4.

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Explanation:

To determine the number of hydrogen atoms in the container, we need to know the number of water molecules present in the container.

At standard temperature and pressure (STP), which is defined as a temperature of 273.15 K and a pressure of 1 atmosphere (atm), one mole of any gas occupies a volume of 22.4 liters. Therefore, the number of moles of water vapor present in the container can be calculated as:

n = V/22.4

where V is the volume of the container in liters. Substituting the given value, we get:

n = 2.80/22.4 = 0.125

So, there are 0.125 moles of water vapor in the container.

Now, to determine the number of hydrogen atoms present in the container, we need to know the number of water molecules in the container, since each water molecule contains two hydrogen atoms. The number of water molecules can be calculated as:

N = n * N_A

where N_A is Avogadro's number, which is equal to 6.022 x 10^23 molecules per mole. Substituting the values, we get:

N = 0.125 * 6.022 x 10^23 = 7.528 x 10^22

So, there are 7.528 x 10^22 water molecules in the container, and since each water molecule contains 2 hydrogen atoms, the total number of hydrogen atoms in the container is:

2 * N = 2 * 7.528 x 10^22 = 1.506 x 10^23

Therefore, there are 1.506 x 10^23 hydrogen atoms present in the container.

Avogadro's Law is the notion that one mole of any gas has the same volume at STP (Standard Temperature and Pressure). identical volumes of gases at the same pressure and temperature have an identical number of molecules, according to Avogadro's Law.

This means that at STP, a mole of any gas will take up the same amount of space—22.4 liters—as another mole.

Avogadro's Law may therefore be used to determine the volume of hydrogen gas at STP, which is 22.4 liters for each mole. This is due to Avogadro's Law, which states that one mole of any gas at STP has the same number of particles (6.022 x 1023) and takes up the same amount of space (22.4 liters).

Avogadro's Law

A fundamental gas law called Avogadro's Law describes the correlation between a gas's volume and the number of particles it contains. identical volumes of gases at the same pressure and temperature have an identical number of molecules, according to this statement.

This indicates that one mole of any gas will have the same volume as 22.4 liters at standard temperature and pressure (STP), which is defined as 0°C (273.15 K) and 1 atmosphere (atm) of pressure. A mole, or 6.022 x 1023 particles, or Avogadro's number, is a unit of measurement that denotes a certain number of particles.

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To solve this problem, we can use the conservation of mass and energy principles. The mass balance equation can be written as:

1.96 kg steam at 20 bar = x kg steam at T₁ and 20 bar + (1-x) kg steam at T₂ and 10 bar

Solving for x gives:

x = 0.9014

Therefore, 0.9014 kg of the total steam mass comes from the superheated steam stream, while the remaining 0.0986 kg comes from the saturated steam stream.

The energy balance equation can be written as:

(1.96 kg)(h₁) = (0.9014 kg)(h₁) + (0.0986 kg)(hf₂) + (product stream)

Solving for h₁, we get:

h₁ = 3449 kJ/kg

Similarly, solving for T₂ using the saturation table for steam at 10 bar gives:

T₂ = 179.9°C

To find T₁, we can use the steam tables to look up the enthalpy of superheated steam at 20 bar and use the energy balance equation to solve for T₁:

(1.96 kg)(3188 kJ/kg) = (0.9014 kg)(3449 kJ/kg) + (0.0986 kg)(hf(T₂)) + (product stream)

Solving for T₁ gives:

T₁ = 511.6°C

If heat is being lost from the blender to the surroundings, our estimate of T₁ would be too high. This is because if the system is losing heat, the energy balance equation would be incorrect since it assumes that all the energy input is used to heat up the steam. Thus, T₁ would be overestimated, and the actual value would be lower.

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Answer:

bar graph

Explanation:

because of the fact that the data is shown in such a way that a line graph would not work, you need to graph the data for each individual time

Answer:

The formula for calcium phosphate is Ca3(PO4)2.

(i) The type of bond formed between N and B is a coordinate covalent bond or a dative bond. This is because the lone pair of electrons on the nitrogen atom is donated to the boron atom to form a bond.

(ii) The F-B-F bond angle in this molecule is expected to be approximately 120 degrees.

(iii) This is because the molecule has a trigonal planar geometry, with the boron atom at the center and three fluorine atoms at the corners of an equilateral triangle. The lone pair of electrons on the nitrogen atom is also located in the same plane as the three fluorine atoms, and it occupies one of the corners of the trigonal planar arrangement. Therefore, the F-B-F bond angle is expected to be approximately 120 degrees, which is the ideal bond angle for a trigonal planar geometry.

To determine the sulfate ion concentration of the resulting solution, we first need to calculate the moles of sulfate ions in each solution, and then add them together.

For the CuSO4 solution:

moles of CuSO4 = concentration x volume in liters

moles of CuSO4 = 1.50 mol/L x 0.075 L

moles of CuSO4 = 0.1125 mol

Since there is 1 mole of sulfate ion for every mole of CuSO4, the moles of sulfate ion in the CuSO4 solution is also 0.1125 mol.

For the Co2(SO4)3 solution:

moles of Co2(SO4)3 = concentration x volume in liters

moles of Co2(SO4)3 = 1.00 mol/L x 0.050 L

moles of Co2(SO4)3 = 0.050 mol

Since there are 3 moles of sulfate ion for every mole of Co2(SO4)3, the moles of sulfate ion in the Co2(SO4)3 solution is 0.050 mol x 3 = 0.150 mol.

Now, we can add the moles of sulfate ions from each solution together to get the total moles of sulfate ions in the resulting solution:

total moles of sulfate ion = moles of CuSO4 + moles of Co2(SO4)3

total moles of sulfate ion = 0.1125 mol + 0.150 mol

total moles of sulfate ion = 0.2625 mol

To find the sulfate ion concentration of the resulting solution, we need to divide the total moles of sulfate ion by the total volume of the resulting solution, which is the sum of the volumes of the two solutions:

total volume = 75.0 mL + 50.0 mL

total volume = 125.0 mL or 0.125 L

sulfate ion concentration = total moles of sulfate ion / total volume

sulfate ion concentration = 0.2625 mol / 0.125 L

sulfate ion concentration = 2.10 mol/L

Therefore, the sulfate ion concentration of the resulting solution is 2.10 mol/L.

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When the samples A and B are combined, the Kinetic energy of the particles will increase and in the second experiment option (C) best describes the thermal equilibirum on a microscopic level.

Kinetic energy, which may be seen in the movement of an item or subatomic particle, is the energy of motion. Kinetic energy is present in every particle and moving object. Kinetic energy is a type of power that a moving object or particle possesses. An item accumulates kinetic energy when work, which involves the transfer of energy, is done on it by exerting a net force. A moving object or particle has kinetic energy, which depends on both its mass and its rate of motion. The type of motion can be vibration, rotation on an axis, translation (or travel along a path from one place to another), or any combination of these.

A body's translational kinetic energy, or 1/2mv², is determined by multiplying its mass, m, by the square of its velocity, v.

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Answer:

When samples A and B were combined, the kinetic energy of the particles transferred from the particles with higher kinetic energy (from beaker A) to the particles with lower kinetic energy (from beaker B). This transfer of kinetic energy resulted in the particles in the combined water sample having a new, average temperature of 35°C.

Explanation :

The statement that best supports thermal equilibrium on a microscopic scale is: A. Beaker A has molecules of higher kinetic energy. These molecules collide with molecules from beaker B and transfer some of their energy. Energy is transferred until the average potential energy of the molecules from both samples are the same. This statement explains how the transfer of kinetic energy occurs between the molecules in beakers A and B, resulting in the eventual thermal equilibrium of the combined water sample.

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Answer:

I suppose it's 4Fe + 3O2 + 6H2O → 4Fe(OH)3

Explanation:

Iron needs both water and oxygen to oxidise and rust