a metal x reacts with oxygen to form metal oxide y used in cement industry. y dissolves in water producing z with hissing sound which is used for whitewashing.the clear solution of z reacts with co2 to form white precipitate.identify x, y, z and write chemical reactions involved

S- is present at a concentration of 2 10(-13) M, whereas H+ is present at a concentration of 0.05 M.

The number of moles in relation to the substance's volume is known as the concentration.

H2S is entirely ionized in the solution, as we are all aware of.

the chemical formula H2S ——- 2(H+) + S2-

Concentration = volume / moles

It is discovered that the concentration of H+ ions and H2S are equivalent.

[H+] = [H2S] = 0.05M

Being aware of that

[H+] [OH-] = 10^(-14) (-14)

[OH-] = 10^(-14) / 0.05

[OH-] = 2 × 10^(-13) (-13)

The concentration of S- in is therefore 2 10(-13) M, while the concentration of H+ ion is 0.05M.

The complete question is,

Determine how much of each species there is in an H2S solution with a concentration of 0.05 m.

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ΔH° for the reaction Fe3O4(s)+2C (graphite) → 3 Fe(s) + 2CO2(g) is - 725kj/mol⁻¹.

Hess's law states that if a process can be showed as the sum of two or more steps, the enthalpy change for the overall process is the sum of the ΔH values for each step.

Fe3O4(s)+2C (graphite) → 3 Fe(s) + 2CO2(g),    

We invert (1) and change the sign of  ΔH

Fe3O4(s)   →  3Fe(s)+3CO2(g)  ΔH = 1118

We multiply (2) by 3

2C(g)+1/2O2(g) → CO2(g)         ΔH = - -394   (2)

3CO(g)+3/2O2(g)→3CO2(g)         ΔH = 1118

We add (1) and (2)

Fe3O4(s)  →  3Fe(s)+3CO2(g)  ΔH = 824.2 kJ

3CO(g)+3/2O2(g)→3CO2(g)         ΔH = -848.1 kJ

Fe3O4(s)+2C (graphite) → 3 Fe(s) + 2CO2(g),    

Therefore, ΔH° = - 725kj/mol⁻¹

Thus,  ΔH° for the reaction Fe3O4(s)+2C (graphite) → 3 Fe(s) + 2CO2(g) is - 725kj/mol⁻¹.

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Given the number of moles of carbon in the compound is 0.074 and the number of moles of oxygen is 0.148 moles. Convert these numbers to whole number ratios we get the empirical formula of the compound as CO₂.

The empirical formula of a compound is derived from the number of moles of the constituent elements of the compound. The mole ratio of the elements give  the subscripts in the formula.

Given,

number of moles of carbon in the compound = 0.074 moles

number of moles of oxygen = 0.148 moles

mole ratio of C to O is 0.074 : 0.148.

Divide both numbers by 0.074 to get whole numbers. we will obtain 1:2.

Hence, carbon and oxygen are in the ratio of  1:2 and the formula of the compound is CO₂.

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All organisms require an influx of substances from their habitat to meet their nutritional  needs for chemical elements and energy.

Every organism in the earth needs to meet the basic needs for air, food , water and shelter for their growth. Irrespective of the type of organism and level of development all organisms need an influx of nutrition to their body.

Certain microorganism species are referred to as facultative. These organisms can develop with or without oxygen present. Certain types of bacteria are microaerophilic, which means they can flourish in environments with little oxygen.

The nutrients which are needed in high quantity are called macronutrients. Nutrients which have to be intaken in small quantities or in traces are called micro nutrients or trace nutrients.

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10_20 20_30 30_40 40_50 50_60

One could incorporate a control experiment using an identical setup but without the gas to confirm that the gas is responsible for the color change.

To verify that the gas is responsible for the color change, a control experiment can be conducted by setting up an identical experiment but without the gas. This would involve placing the same amount of fresh beans in a test tube, adding the same amount of sodium hydroxide solution, and observing the change in color.

If the control experiment does not produce the same results, then it can be concluded that the gas is responsible for the color change. One could also include a test where a different gas, such as carbon dioxide, is added to the experiment and observe if the same color change occurs.

By doing these experiments, one can rule out other factors and prove that the gas is the cause of the change in color.

This question is related to "Lab 9: Cellular Respiration, Experiment 2: Aerobic Respiration in Beans, Post Lab Question."

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To calculate the change in temperature of the cold water and the hot water is

ΔT = T (final) - T (initial)

To calculate the change in temperature you need to know the initial temperature of each water sample and the final temperature after they are mixed.

where ΔT represents the change in temperature, T final represents the final temperature, and T initial represents the initial temperature.

For example, if you have 50 grams of cold water at 10°C and 50 grams of hot water at 80°C, and after mixing, the final temperature is 60°C, then you can calculate the change in temperature for the cold water as follows:

ΔTcold water = T final - T initial cold water = 60°C - 10°C = 50°C

And for the hot water:

ΔT hot water = T final - T initial hot water = 60°C - 80°C = -20°C

the change in temperature of the cold water is positive, which means that its temperature has increased, while the change in temperature of the hot water is negative, which means that its temperature has decreased.

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The conversion factors to the conversions that they would be used for as follows:

1.moles/grams ⇒ d. mass to mole

2.grams/moles ⇒ a. mole to mass

3.atoms/grams ⇒ e. mass to atom

4.moles/atoms ⇒ c. atoms to mole

5.atoms/moles ⇒ b. moles to atoms

The term mole is defined as the amount of substance of a system which contains as many elementary entities.

One mole of any substance is equal to 6.023 × 10²³ units of that substance such as atoms, molecules, or ions. The number 6.023 × 10²³ is called as Avogadro's number or Avogadro's constant.

The mole concept can be used to convert between mass and number of particles.

Thus, The conversion factors to the conversions that they would be used for moles/grams ⇒ mass to mole.

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True, has two naturally occurring isotopes lithium-6 and lithium-7 has a natural abundance of 7.5%.

Lithium has two naturally occurring isotopes, lithium-6 and lithium-7. Lithium-6 is a stable isotope, meaning it does not undergo radioactive decay, and has a natural abundance of 7.5%. The heavier isotope, lithium-7, is an unstable isotope with a natural abundance of 92.5%. It is a low-energy beta emitter with a half-life of 8.5 hours. The two isotopes behave differently in chemical reactions and can be used to trace the origin of materials. Lithium-6 is used in nuclear reactors to control the release of energy, and Lithium-7 is used in Nuclear Magnetic Resonance imaging and spectroscopy. Both isotopes of lithium are essential for many industries, including aerospace and pharmaceuticals.

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The element that has properties most similar to those of potassium is rubidium (Rb).

Potassium (K) and Rubidium (Rb) are both members of Group 1 in the periodic table, also known as the "alkali metals". This group of elements is characterized by its high reactivity, low ionization energy, and the presence of a single valence electron. As a result, both potassium and rubidium are highly reactive and easily form compounds with other elements. In terms of physical properties, both potassium and rubidium are soft, silvery-white metals that are relatively low in density and have relatively low melting and boiling points. Furthermore, they are both highly soluble in water and are highly reactive with air, forming a protective oxide layer that helps to prevent further corrosion. In summary, potassium and rubidium have very similar properties and are both highly reactive, soft, silvery-white metals.

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NAG3 is able to hydrogen bond to the side chains of all of the amino acids except for the amino acid at the position of the 5' end of the peptide bond. This is because the 5' end of the peptide bond is typically blocked by the N-terminal amino group of the  N- acetyl glucosamine molecule.

NAG3 is a molecule found in some polysaccharides (carbohydrates) and is able to interact with amino acids in a protein through hydrogen bonding. This interaction between NAG3 and amino acids can occur with all of the side chains of the amino acids, except for the one at the position of the 5' end of the peptide bond. The peptide bond is a chemical bond between two amino acids that links them together in a protein. The 5' end of the peptide bond refers to the end of the bond that is closer to the N-terminal (beginning) of the protein.

The reason why NAG3 cannot hydrogen bond with the amino acid at the 5' end of the peptide bond is because this end is typically blocked by the N-terminal amino group of the N-acetylglucosamine molecule. This blocking effect prevents NAG3 from forming a hydrogen bond with the amino acid at this position, which is why NAG3 can hydrogen bond to all other side chains of the amino acids except for this one.

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A precipitate occurs when a 29.3 ml sample of a 1.4 m potassium chloride solution and a 36.8 ml sample of a 1.06 m lead(ii) nitrate solution are combined. The solid is gathered, dried, and determined to weigh 2.00 g. 36.70% is the percent yield.

To calculate the percent yield of the reaction, we need to compare the actual yield with the theoretical yield, and express the result as a percentage.

According to the balanced equation, 2 moles of KCl react with 1 mole of Pb(NO3)2 to produce 1 mole of PbCl2. Therefore, the theoretical yield of PbCl2 is:0.0196 mol.

The molar mass of PbCl2 is 278.10 g/mol, so the theoretical mass of PbCl2 is:5.454

The actual yield of PbCl2 is given as 2.00 g. Therefore, the percent yield is:

percent yield = actual yield / theoretical yield x 100% = 2.00 g / 5.454 g x 100% = 36.70%

Rounding to two decimal places, the percent yield is 36.70%.

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The IUPAC name of compound is propanoic acid.

The purpose of the IUPAC system of nomenclature is to establish an international standard of naming compounds to facilitate communication.

The goal of the system is to give each structure a unique and unambiguous name, and to correlate each name with a unique and unambiguous.

Alkanes are the family of saturated hydrocarbons, that is, molecules containing carbon and hydrogen connected by single bonds only. These molecules can be in continuous chains (called linear or acyclic), or in rings (called cyclic or alicyclic). The names of alkanes and cycloalkanes are the root names of organic compounds.

Therefore, The IUPAC name of compound is propanoic acid.

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The sum of the masses of all substances involved

The number of atoms of each kind

We know that according to the law of the conservation of mass, mass can neither be created or destroyed but can be changed from one form to the other.

This is how we arrive at the general rule that the number of atoms on both sides of the reaction equation would have to be the same for all the atoms that are taking part in the reaction. Thus we can see that the parameters stated above must be the same on both sides.

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Missing parts;

Which quantity or quantities must always be the same on both sides of a chemical equation? Check all that apply. Check all that apply.

the number of molecules of each kind

the sum of the masses of all substances involved

the number of moles of each kind of molecule

the number of atoms of each kind

5.33 moles Liters of gas is 3.21 x 1024 molecules of carbon monoxide.

1 mole contains 6.02×[tex]10^{23}[/tex]

X×6.02×[tex]10^{23}[/tex] = 3.21×[tex]10^{24}[/tex]

X= 3.21×[tex]10^{24}[/tex]/6.02×[tex]10^{23}[/tex] = 0.533×10= 5.33 moles

A molecule is a collection of two or greater atoms held together by attractive forces called chemical bonds; relying on context, the term can also or might not consist of ions that fulfill this criterion.

A molecule may be homonuclear, this is, it includes atoms of one chemical element, e.g. atoms inside the oxygen molecule (O2); or it may be heteronuclear, a chemical compound composed of a couple of detail, e.g. water ( hydrogen atoms and one oxygen atom; H2O). within the kinetic theory of gases, the time period molecule is frequently used for any gaseous particle no matter its composition. This relaxes the requirement that a molecule includes extra atoms because the noble gases are character atoms.

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The main site of action of benzodiazepine hypnotics is various GABA receptors present throughout the CNS.

Benzodiazepines are defined as a group of CNS depressants which induces feelings of calm (anxiolysis), drowsiness and sleep. They act by facilitating the binding strength of the inhibitory neurotransmitter GABA at various GABA receptors throughout the CNS.

Generally, the benzodiazepines act by increasing the affinity of the GABA receptor for its ligand, thereby augmenting the inhibitory effect of a given concentration of GABA.

The anxiolytic effects of Benzodiazepines are believed to be mediated through Benzodiazepines receptors which are located in the limbic system, and myorelaxant properties are mediated through α2-containing receptors present in the spinal cord and motor neurons.

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Answer: They are both chemical changes.

Explanation:

Being a weak acid (Ka = 5.6x104), the nitrous acid reacts with NaOH as follows: NaOH (l) + HNO2 = NaNO2 (aq) + H2O.

A 0.15 m naoh solution is used to titrate 100 ml of 0.15 m nitrous acid (HNO2). The pH of the initial solution is 2.04, 3.85 for the equivalence point, 8.06 for the point at which 80.0 ml of the base has been added, and 11.56 for the point at which 105 ml of the base have been added. There is initially simply a 0.12M HNO2 solution. Like Ka is: Ka is equal to [H+] [NO2]/[HNO2]. When the ions [H+] and [NO2] come from the same equilibrium, [H+] = [NO2] = x, 5.6x10⁻⁴ = X² / 0.15M. 8.4x10⁻⁵ = X². X = [H⁺] = 9.165x10⁻³M. Since pH = -log [H+], pH = 2.04.

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The difference between the critical angles for red and green light is equal to the difference between the sine of the two angles, or sin(θc, red) - sin(θc, green).

The critical angle is the angle of incidence (angle between the incoming light and the normal to the surface) at which the refracted ray is just grazing the surface and no further refraction occurs. Beyond this angle, the light will start to reflect back into the medium from which it came, and not enter the second medium. The critical angle is determined by the refractive indices of the two media and is dependent on the ratio of their refractive indices.

The critical angle for red light in flint glass surrounded by air is given by the equation sin(θc) = nair/nflint, where nair is the refractive index of air (approximately 1) and nflint is the refractive index of flint glass (1.662 for red light). The critical angle for green light is calculated in the same manner, using the refractive index of flint glass for green light (1.674).

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Name and Title: Miles Junior

[Instructor's Name]: Tom Hales

[Date] - February, 7th , 2023.

Plate Tectonics Lab Report (see attached document)

Objective(s): The purpose of this lab was to investigate the interactions between continental and oceanic plates at convergent, divergent, and transform boundaries around the world and to record observations in the lab report.

At divergent plate boundaries, geological events such as earthquakes, faults, and ocean formation occur. At convergent plate boundaries, earthquakes, faults, mountains, and volcanoes occur. At transform plate boundaries, earthquakes and faults occur.

Through the years, these geological processes and interactions have changed the Earth's surface by creating new land, causing earthquakes, and creating new oceanic and continental crust. This lab showed that the interactions between plates at different boundaries have different outcomes and have a significant impact on the Earth's surface over time.

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The number of Titanium atoms that has a density of 4.50 g/cm³ and edge length cube of 2.78 inches equals to 1.99 × 10²⁵atoms

The ratio of a substance's mass to its volume is the formula for determining its density. Density is measured in kilograms per cubic meter. We can use the following formula to get the density of a cube as it is shown here:

Density = Mass of cube ÷ Volume of cube

First, we need to convert the Edge length of cube’s unit

2.78 inches = 7.0612 cm

Mass of Titanium = Density × Volume

Mass = Density x (Edge length)³

Mass = 4.5 g/cm³ × (7.0612 cm³)³

Mass = 1584.33877 g

Moles of Titanium = Mass of Titanium ÷ Molar mass of Titanium

Moles of Titanium = 1584.33877 g ÷ 47.867 g/mol

Moles of Titanium = 33.099 mol

Thus, the number of atoms in Titanium would be:

Atoms of Titanium = 33.099 mol × 6.022×10²³ atoms/mol

Atoms of Titanium = 1.99 × 10²⁵ atoms

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No, the balloons filled with different gaseous compounds will not have the same mass. The mass of a gas is dependent on its density, which is a function of its molar mass and its pressure and temperature.    

Different gaseous compounds have different molar masses, and therefore, different densities at a given pressure and temperature. As a result, the mass of a gas depends on the identity of the gas, not just on its volume.For example, if one balloon is filled with hydrogen gas, another with nitrogen gas, and a third with carbon dioxide gas, all at the same pressure and temperature, they will not have the same mass even though they have the same volume. The mass of the hydrogen gas will be the lowest due to its low molar mass, the nitrogen gas will have a higher mass, and the carbon dioxide gas will have the highest mass due to its higher molar mass.

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Examining the graph the missing parts are

21. pressure

22. Solid

23. condensation

24. gas

A phase diagram is a graphical representation of the conditions (temperature, pressure, and composition) under which different phases of a substance exist in thermodynamic equilibrium with each other. It is a powerful tool for understanding the behavior of a substance under varying conditions, and for predicting the conditions under which a particular phase of the substance will form or transform into another phase.

A typical phase diagram shows the boundary lines separating different phases, such as solid, liquid, and gas, and indicates the conditions under which each phase is stable.

The phase diagram can also indicate the conditions under which a substance will undergo a phase transition, such as melting or boiling, and the conditions under which the substance will be in a single phase, such as a supercritical fluid.

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a) This is a Combustion reaction.

b) The percentage of  yield of this reaction is 51.39%

What is a chemical reaction?

A chemical reaction is the transformation of one or more substances (the reactants) into one or more distinct substances (the products). Chemical elements or chemical compounds make up substances. In a chemical reaction, the atoms that make up the reactants are rearranged to produce various products.

Given chemical reaction

2 C₂H₂ (g) + 3 O₂ (g) - 2 CO₂ (g) + 2 H₂0

A fuel and an oxidant, typically atmospheric oxygen, engage in a high-temperature exothermic redox chemical reaction known as combustion or burning, which results in the production of oxidized, frequently gaseous products in a mixture known as smoke.

In the given reaction produce a gas that is carbon di oxide and water. Thus it is a Combustion reaction.

The mass of H₂O is (2×2) + 16 = 18 grams.

The mass of water in balanced reaction is (2×18) grams = 36 grams

The formula of percent yield is

%yield = (actual yield/theoretical yield) x 100.

Actual yield = 18. 5 g

Theoretical yield = 36 grams

%yield = (18.5/36) x 100

%yield = 51.39%

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(SOMEONE ELSE'S ANSWER TO THE SAME QUESTION I FOUND I HOPE THIS HELPS!) Given:

mass of Na₂SO₄ = 25.0 g

Required:

moles of Na

number of Na particles

Solution: (moles of Na)

Step 1: Calculate the molar mass of Na₂SO₄.

molar mass of Na₂SO₄ = (22.99 g/mol × 2) + (32.07 g/mol × 1) + (16.00 g/mol × 4)

molar mass of Na₂SO₄ = 142.05 g/mol

Step 2: Calculate the number of moles of Na by using dimensional analysis.

Since there are 2 mol of Na in 1 mol of Na₂SO₄, the number of moles of Na is

Solution: (number of Na particles)

The pH of a solution is determined by the concentration of hydrogen ions (H+) in the solutio The pH in beaker B is 6.45.

Concentration is the ability to focus and maintain attention on a task or thought for an extended period of time. It involves using mental effort to maintain focus and block out distractions. Concentration is important for studying, problem-solving, and other activities that require sustained attention. It can be trained and improved with practice. Strategies such as eliminating distractions, breaking tasks into smaller steps, and taking regular breaks can help to improve concentration.

In Beaker A, we can see that the concentration of H3O+ is greater than Beaker B, which indicates that Beaker A has a lower pH. Since the pH in Beaker A is 4.45, this implies that the pH in Beaker B must be higher. To calculate the exact pH of Beaker B, we would need to know the exact concentration of H3O+ in each beaker.

The pH of a solution is determined by the concentration of hydrogen ions (H+) in the solutio The pH in beaker B is 6.45.

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The milligrams of the gas are formed if 10.0ml of 3.00% hydrogen peroxide solution decomposes, The density of the solution is 1.00 g/mL is 300 mg.

The equation is as follows :

2H₂O₂(l)   ---->   2H₂O(l)   +   O₂(g)

The density of the solution = 1 g/mL

The volume of the water = 100 mL

The volume of the H₂O₂ = 10 mL

The mass of the hydrogen peroxide = 3 g

2 moles of the hydrogen peroxide produces the 1 mole of the oxygen gas.

The mass of the O₂ =   (10 mL × 3 g of H₂O₂ ) / 100 mL

                                = 0.3 g = 300 mg

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the mass of methanol is  22.2g  and 33.8g  [tex]H_2O[/tex]

The idea here is that you need to use the definition of mole fraction to find a relationship between the number of moles of methanol,

, and the number of moles of water.

mole fraction is defined as the ratio between the number of moles of a component i of a solution and the total number of moles present in that solution.

[tex]X_i=\frac{No\: of\: moles\: of\: i}{total \: no \: of \:moles}[/tex]

Now,  solution contains methanol, your solute, and water, your solvent. If you take x to be the number of moles of methanol and y to be the number of moles of water,

the mole fraction of methanol will be= [tex]X_{Ch_3oh}=\frac{x}{x+y} =0.270 \rightarrow(1)[/tex]

[tex]X_{Ch_3oh}=\frac{x\times32.042}{1} =32.042x[/tex]

the same for water

[tex]Y_{H_2O}=\frac{y\times18.015}{1} =18.015y[/tex]

You thus have

32.042x +18.015y=56    [tex]\rightarrow(2)[/tex]

now two equations with two unknowns. Use equation (1)

x=0.270 ×  (x +y)

0.730x=0.270y

x=[tex]\frac{0.270}{0.730}y[/tex]

Plug this into equation (2)

32.042 ([tex]\frac{0.270}{0.730}y[/tex] ) +18.015y=56

11.85y + 18.015y =56

y=[tex]\frac{56}{11.85+18.015}=1.875[/tex]  

This will give you

[tex]x=\frac{0.270}{0.730} \times1.875=0.6935[/tex]

Use the molar masses of the two species to convert the number of moles to grams

0.6935 × 32.0412 =22.2g [tex]Ch_3Oh[/tex]

1.875 × 18.015=33.8g  [tex]H_2O[/tex]

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The communication between neurons is accomplished using energy and the type of energy is electricity and chemicals.

Neurons communicate with each other in connections called synapses, a process called synaptic transmission. At a synapse, one neuron sends a message to another cell, the target neuron. Most synapses are chemical. These synapses communicate using chemical messengers. Other synapses are electrical. At these synapses, ions flow directly between cells. Neurons communicate with each other using electrical events called "action potentials" and chemical neurotransmitters. Neurotransmitters are chemical messengers that the body cannot function with. Their job is to send chemical signals ("messages") from one neuron (nerve cell) to the next target cell. The next target cell could be another nerve cell, muscle cell, or gland. Thus, neurons use both electrical charge and chemicals called ions to communicate with each other.

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The element that is not one of the four elements that make up the vast majority (96%) of molecules in our body is gold. Option C is correct.

The four elements that make up the vast majority (96%) of molecules in our body are carbon, oxygen, hydrogen, and nitrogen. These elements form the building blocks for molecules such as carbohydrates, lipids, proteins, and nucleic acids, which are essential for life.

While gold is a chemical element and can be found in trace amounts in the human body, it is not one of the four elements that make up the majority of molecules in our body.

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--The given question is incomplete, the complete question is

"Which is not one of the four elements that make up the vast majority (96%) of molecules in our body? A) Carbon B) Oxygen C) Gold D) Hydrogen E) Nitrogen"--