how many orbitals are completely filled in an atom that has 12 electrons? the electron configuration is 1s 2 2s 2 2p 6 3s 2

Baking soda (sodium bicarbonate) is a kitchen staple that can do wonders for cleaning smelly or clogged clothes, appliances, and even drains. As a natural mineral compound, baking soda can dissolve mineral deposits and organic matter such as grease.

Procedure to unclog a shower drain with baking soda and vinegar:

1. Heating Boiling Water

Heat boiling water in a kettle on the stove or in a large flow-through measuring cup in the microwave.

2. Put boil water and Dish soap into drain:

Pour dish soap down the drain and carefully drain the boiling water. Dishwashing liquid can help clear up greasy blockages.

3. Pour Baking Soda Down the Drain

Pour one cup of baking soda down the drain. To do this, it is difficult to pour water directly into the drain using a measuring cup or funnel if the drain is small.

4. Pour in vinegar

Pour one cup of distilled white vinegar down the drain. Don't be surprised by the sound response that occurs. Baking soda is an alkali, whereas vinegar is a weak acetic acid. When they mix, they react rather dramatically, neutralizing each other. The hiss you hear is often a response to knocking on a blockage in the drain.

5. Rinse with plenty of hot water.

Wait 5 minutes when hissing stops. Use this time to boil two cups of water. Rinse the drain with this extra boiling water. If water is leaking from the drain, run hot tap water to flush the debris down the drain. If it doesn't merge, repeat the previous step.

Complete Question:

How To Unclog Drain With Baking Soda And Vinegar?

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The right response is (a) 0.0863 nm3. The equation V = a2c3/4 may be used to calculate the volume of the unit cell for rhenium.

The following formula may be used to get the volume of the unit cell for rhenium:

The height of the unit cell along the c-axis is given by the formula Volume of HCP unit cell = (3/2) x 3 x a2 x c.

Rhenium's atomic radius is 0.137 nm, hence 2 x 0.137 nm = 0.274 nm may be used to compute the length of one side of the hexagonal base (a).

Rhenium has a c/a ratio of 1.615, which means that c = 1.615a.

By replacing these values in the formula above, we obtain:

HCP unit cell volume is (3/2) x 3 x (0.274 nm)2 x (1.615 x 0.274 nm) = 0.0863 nm3.

As a result, option is chosen because the volume of the unit cell for rhenium is 0.0863 nm3 (a).

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When an electron moves in the direction of electric field its kinetic energy will decreases and potential energy will increase.

When the electron moves along the direction of E, due to the repulsive force, it undergoes deceleration. thus, the kinetic energy diminishments. As external work is done in moving the electron in this direction, its implicit energy will increase.

The implicit energy of the charge in the electric field is given by

U=qφ where q is the charge and φ is the electric implicit corresponding to the electric field.

The electric field is defined mathematically as a vector field that can be associated with each point in space, the force per unit charge wielded on a positive test charge at rest at that point.

The electric field is generated by the electric charge or by time- varying glamorous fields. In the case of infinitesimal scale, the electric field is responsible for the seductive forces between the infinitesimal nexus and electrons which hold them together.

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Answer:

The weak acid will give it's H+

Explanation:

If a strong base is added to a buffer, the weak acid will give up its H+ in order to transform the base (OH-) into water (H2O) and the conjugate base: HA + OH- → A- + H2O. Since the added OH- is consumed by this reaction, the pH will change only slightly.

Water can be defined as saltwater when it contains enough dissolved salts to alter its physical and chemical properties. The minimum concentration of dissolved salts in water that can still be considered saltwater is generally defined as 3.5% or 35 parts per thousand (ppt) by weight.

This concentration is often referred to as the "salinity" of the water, and it represents the total amount of dissolved salts in the water. Salinity is typically measured using a unit called "practical salinity units" (psu), which is equivalent to ppt.

Water with a salinity level below 3.5% is typically considered freshwater. However, it's important to note that the exact threshold for when water is considered saltwater may vary depending on the context. For example, some sources may define saltwater as any water with a salinity level above 1 ppt, while others may use a higher threshold.

In general, the higher the salinity level of water, the more challenging it can be for organisms to survive in it. This is because high levels of dissolved salts can affect the osmotic balance of cells, making it harder for them to regulate the flow of water and nutrients

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The substances that participate in a reaction are called reactants, whereas the substance that forms as a result of a reaction is called a product.

Reactants are the starting materials that are involved in a chemical reaction, which undergo a transformation to form new substances. The reactants are typically shown on the left side of a chemical equation, with an arrow pointing to the right side, where the products are shown.

Products, on the other hand, are the new substances that are formed as a result of the chemical reaction. They are typically shown on the right side of a chemical equation, with an arrow pointing from the reactants on the left side.

Chemical reactions involve the breaking and formation of chemical bonds, which result in the rearrangement of atoms to form new substances with different chemical and physical properties than the reactants. The law of conservation of mass dictates that the total mass of the reactants must be equal to the total mass of the products in a chemical reaction.

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The weight percentages of sodium chloride is 23.1 % and water is 76.9 % in the solution. The theoretical density of the initial concentrated solution is 0.30 g/mL.

The mass of the sodium chloride = 30 g

The mass of the water = 100 mL = 100 g

The total mass = 30 + 100

                         = 130 g

The mass percentage of sodium chloride = (30 / 130 ) × 100 %

                                                                        = 23.1 %

The weight percentage of the water = ( 100 / 130 ) × 100 %

                                                             = 76.9 %

The density of the solution = mass / volume

                                             = 30 / 100

                                            = 0.30 g/mL

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Answer:

Explanation:

The acceleration can be calculated using the following formula:

acceleration = (final velocity - initial velocity) / time

In this case:

acceleration = (3 m/s - 15 m/s) / 2 seconds = -6 m/s^2

So the horse slows down with an acceleration of -6 meters per second squared. Note that the negative sign indicates that the direction of the acceleration is opposite to the direction of motion.

Hydrofluoric acid (HF), and Bromide (Br-) are weak electrolyte, according to the options given. Hence the correct option is (a), and (c) respectively.

A weak electrolyte is a substance that only partially dissociates into ions when dissolved in a solvent. The extent of dissociation depends on the concentration of the electrolyte in the solution and the strength of the bond between the ions.

Based on this definition, the following substances can be classified as weak electrolytes:

a. Hydrofluoric acid (HF) - Hydrofluoric acid is a weak acid that only partially dissociates into ions in aqueous solution.

c. Hydrogen Bromide (HBr) - Hydrogen Bromide is a weak base that dissociates only slightly in water.

On the other hand, the following substances are strong electrolytes and dissociate completely into ions when dissolved in water:

b. Hydrochloric acid (HCl) - Hydrochloric acid is a strong acid that dissociates completely into hydrogen (H+) and chloride (Cl-) ions in water.

d. Hydrogen iodide (HI) - Hydrogen iodide is a strong acid that dissociates completely into hydrogen (H+) and iodide (I-) ions in water.

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The "convergent plate boundary" is the kind of plate boundary that the student is simulating.

This zero-width check between two letters identifies a word boundary. A word character and a non-word letter must be present for the test to be successful. Each figure must appear on one side, regardless of which side they are on.

For illustrate, the "three little pigs" went to the market. Indivisibility: Specify a statement and request that someone "add extra words" to it. This additional item will be entered between the words, not before or after them.

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Answer:

6. KCIO4 -> KCI + 2O2

7.  Ni(OH)2 + H2SO4 → NiSO4 + 2H2O        

8.  4Ga(Cn)3 + 3Sn(BrO3)4 → 3Sn(Cn4) + 4Ga(BrO3)3

9.  3Ca(NO3)2 + 2Fe → 2Fe(NO3)3 + 3Ca              

Explanation:

Balancing a chemical equation involves the following steps:

It is important to balance chemical equations because the law of conservation of mass states that the total mass of the reactants must equal the total mass of the products in a chemical reaction. Balancing chemical equations helps ensure that this law is satisfied.

Different substances have different Luster or ability to reflect light. Luster is the ability of a substance which reflects light.

Luster is defined as the ability of the substance which reflects light. There are two main categories of luster describe how light reflects off a mineral. Those are metallic and submetallic luster and non-metallic luster. Metallic lusters describes minerals that are generally opaque and reflective. This can be described as having the appearance of polished metal. Some metals are also classified as minerals and fall into metallic lusters such as gold, silver, and copper. Luster is said to be a property used to differentiate precious stones and minerals. This describes how light interacts with the surface and structure of a crystallized mineral. It is useful in identifying minerals found in rocks and strata.

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Answer:

thunderstorms

Explanation:

The collision of warm, moist air from the ocean with cool, dry air over land is a common weather pattern that can result in the formation of thunderstorms. When the two air masses meet, the warm, moist air rises rapidly and cools, condensing into clouds and eventually producing precipitation, such as rain or hail. The instability created by this collision of air masses also results in strong, gusty winds and lightning, which are characteristic of thunderstorms. Thunderstorms are most likely to occur in the late afternoon and evening, when the sun has had time to warm the land and create temperature differences between the two air masses.

Allen

The What -if analysis tool will allow you to set one cell to a certain value by changing one other cell is Goal Seek.

The process of basing your input value on an already established output value is known as "goal seeking." The technique involves applying a certain operator to a formula that can be computed using computer software.

The second method is to specify the desired result and ask Excel to determine what adjustments to the inputs would be necessary to make it happen. This is how the goal seek feature operates, and it can provide answers to queries like how many units of a product must be sold to achieve a specific profit level.

The benefits of what-if analysis in Excel include:

By changing the assumptions and tracking the results, an experimenter can produce more informed and precise results.

An experimenter can predict the results of the choice more precisely.

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If lithium hydroxide reacts with gaseous carbon dioxide to form solid lithium carbonate and liquid water. then 0.915 g of carbon dioxide would react with 1.00 g of lithium hydroxide.

The balanced chemical formula for the reaction of carbon dioxide and lithium hydroxide is:

Li2CO3 + H2O = 2 LiOH + CO2.

According to the equation, which is balanced, two moles of LiOH and one mole of CO2 combine to form one mole of Li2CO3.

We must convert the mass of LiOH to moles in order to determine how much CO2 is needed to react with 1.00 g of LiOH. LiOH has a molar mass of:

Lithium's atomic mass is 6.94 and its atomic masses are 15.9994, 1.0079, and 23.95 g/mol respectively.

Hence, 1.00 g of LiOH equals:

1.00 g / 23.95 g/mol equals 0.0417 moles of LiOH

The balanced equation states that 2 moles of LiOH and 1 mole of CO2. The amount of moles of CO2 needed to react with 0.0417 mol of LiOH is therefore:

0.0208 mol CO2 = 0.0417 mol LiOH x (1 mol CO2 / 2 mol LiOH)

Lastly, we can use the molar mass of CO2 to convert the quantity of moles of CO2 to grammes, which is:

1 atomic mass of C plus 2 atomic masses of O equals 44.01 g/mol.

44.01 g/mol times 0.0208 mol CO2 equals 0.915 g CO2

Hence, 0.915 g of carbon dioxide and 1.00 g of lithium hydroxide would react.

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After the correct formula for a reactant in an equation has been written, the formula should not be changed.

Reactant is defined as a substance that is present at the start of a chemical reaction. It is written to the left of the arrow in a chemical equation are called reactants. There is a certain way of writing chemical equations. The reactants are written on the left hand side of the equation with the products on the right hand side. There is an arrow points from the reactants to the products to indicate the direction of the reaction. A chemical equation which includes reactant and product describes a chemical reaction. Reactants are the starting materials and the products are the end result of the reaction.

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Answer:

Ellipse

Explanation:

The term that describes the shape of the orbit of a planet is an "ellipse." An ellipse is a geometric shape that represents the path of a planet as it revolves around the sun. The sun is located at one of the two foci of the ellipse, and the planet moves along the elliptical path, constantly being pulled toward the sun by gravity and being held in its orbit by centripetal force. This combination of gravitational and centripetal forces results in an elliptical orbit for each planet in our solar system.

The product of the addition reaction between butanal, CH3-CH2-CH2-CHO, and water is an alcohol, CH3-CH2-CH2-CH(OH)-H, known as butan-1-ol.

This reaction takes place when the slightly positive oxygen atom of the water molecule interacts with the slightly negative carbonyl carbon of the butanal molecule, forming a new covalent bond. This is known as a nucleophilic addition reaction, and the overall equation is shown below:

CH3-CH2-CH2-CHO + H2O → CH3-CH2-CH2-CH(OH)-H + H3O+

This reaction is called a hydration reaction and is a type of nucleophilic addition reaction. The hydroxide ion acts as a nucleophile, donating its electrons to the partially positive carbon of the aldehyde, and displacing the proton. This forms an oxonium ion, which then undergoes a proton transfer with another water molecule, forming the alcohol product.

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comlete question:water is a polar compound that will commonly add to aldehydes. what is the product of an addition reaction between butanal,CH3-CH2-CH2-CHO and water

among the three gases listed, NO2 would have the fastest-moving molecules on average at a given temperature.

According to the kinetic theory of gases, the average kinetic energy of gas molecules is proportional to their absolute temperature. At a given temperature, gases with lighter molecules will have higher average speeds compared to gases with heavier molecules. This is because the lighter molecules have less mass and therefore can move more quickly for a given amount of kinetic energy. Therefore, among the three gases listed, NO2 would have the fastest-moving molecules on average at a given temperature. This is because NO2 has the lowest molecular weight (46 g/mol) compared to HBr (81 g/mol) and C2H6 (30 g/mol). The faster movement of NO2 molecules is reflected in their higher root-mean-square speed, which is a measure of the average speed of gas molecules in a sample. However, it is important to note that the average speed of gas molecules can vary depending on factors such as temperature, pressure, and the specific conditions of the gas sample.

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The results will be biased toward less photosynthesis if there is less carbon dioxide influx in one compartment than in the other chamber. The correct answer is C.

When the airflow in one chamber is less than the other chamber, less CO2 enters the chamber, resulting in a lower CO2 emission level from that chamber.

This may distort the data collected from this camera and lead to inaccurate measurements and conclusions. It is important to ensure that all chambers receive the same amount of air for accurate readings.

To avoid these errors it is important to ensure that all chambers are supplied with the same amount of air. This can be achieved by using the same flow rate for all chambers or by using a flow meter to measure and control the air flow entering each chamber. Consistent and controlled conditions allow researchers to obtain the accurate and reliable data needed to inform scientific conclusions.

The amount of CO2 entering one chamber is reduced when that chamber receives less outside air than the other chamber, resulting in a lower carbon dioxide emission level from that chamber. This can distort the data from that camera and lead to questionable observations and conclusions. It is important to ensure that the air entering each chamber is uniform in order to obtain accurate measurements. To avoid this mistake, it is important to ensure that the airflow to each chamber is uniform. This can be done in one of two ways: maintaining a constant flow rate within each chamber or using a flow meter to control and manage the airflow.

Complete Question:

Recall that your chambers had a set amount of CO 2 entering each chamber and then you measured how much CO 2 was exiting the chamber. Suppose you conducted your experiment and discovered one of your chambers had a lower in-flow of air relative to the other chambers. What would this do to your data in that chamber?

a. It would not change the results.

b. It would bias the results toward more respiration.

c. It would bias the results toward less photosynthesis.

d. It would bias the results toward more photosynthesis.

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Covalent bonding is a form of bonding that involves de-localized electrons. Two or more atoms share one or more pairs of electrons in covalent bonding to produce a more stable electron.

configuration. Delocalization occurs when the electrons involved in the bonding are not localized between two specific atoms but instead spread out over the entire molecule. Electron delocalization happens in molecules with pi bonds or aromatic systems. Pi bonds form when two p orbitals overlap sideways, allowing electrons to be shared over a greater region, whereas aromatic systems contain a ring of atoms that share electrons in a delocalized manner.Covalent bonding is a form of bonding that involves de-localized electrons. Two or more atoms share one or more pairs of electrons in covalent bonding to produce a more stable electron. Delocalized electrons are a common characteristic of many organic molecules.

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Answer:

The student should take the average of the results from all four trials.

Explanation:

Answer:

The student should take the average of the results from all four trials.

Explanation:

The correct option is to take the average of the results from all four trials. This will give the most accurate representation of the boiling point of water, as it takes into account any measurement errors or variations. The value closest to 100°C or the maximum value of the results could be skewed due to a large measurement error or an outlier. Taking the average of the minimum and maximum value of the results is also not ideal as it does not fully consider the results from all four trials.

ALLEN

As the molarity of a solution increases, the absorbance readings of the solution typically increase.

This is because an increase in molarity generally corresponds to an increase in the concentration of the absorbing species in the solution, which in turn leads to an increase in the number of absorbing particles that can interact with the incident light.

The relationship between absorbance and concentration of a solution is described by the Beer-Lambert law, which states that the absorbance of a solution is proportional to the concentration of the absorbing species and the path length of the light through the solution. Thus, an increase in the concentration of the absorbing species (i.e. the molarity of the solution) leads to an increase in the number of particles that can interact with the light, resulting in a higher absorbance reading.

It's worth noting that this relationship between molarity and absorbance is not always linear, and may depend on the specific properties of the absorbing species and the solvent in which it is dissolved. Additionally, if the concentration of the absorbing species becomes too high, the solution may become opaque and the absorbance readings may no longer be meaningful.

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Molality is the number of moles of solute per kilogram of solvent and is a temperature-independent unit of concentration that is used in many applications in chemical and biological systems.

The term for the amount of solute in moles per kilogram of solvent is "molality." Molality is defined as the number of moles of solute per kilogram of solvent. It is a unit of concentration that is used in chemical and biological systems, especially in the study of solutions.

Molality is often used instead of other units of concentration, such as molarity, because it is temperature-independent. This means that the molality of a solution does not change with changes in temperature, whereas the molarity of a solution does change with temperature. This property makes molality a useful unit for many applications, such as calculating freezing point depression, boiling point elevation, and osmotic pressure.

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The temperature of a 5.50 L sample of NH₃ gas is 22 °C. The   resulting temperature in kelvin if the volume is reduced to 3.40 l at the constant pressure is 286.6 K.

The initial temperature, T1 =  22 °C

The initial volume, V1 = 5.50 L

The final temperature , T2 = ?

The final volume , V2 = 3.40 L

The gas law is expressed as follows :

V1 /T1 = V2 / T2

5.50 / 22 = 3.40 / T2

0.25 = 3.40 / T2

T2 = 13.6 °C = 286.6 K

Thus, the final temperature of the gas is 13.6 °C IS 286.6 K.

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there are approximately 4.069 x [tex]10^{23}[/tex] iron atoms in a hemoglobin molecule.

The number of iron atoms in a hemoglobin molecule can be calculated as follows:

First, determine the mass of iron in a single hemoglobin molecule:

mass of iron = 0.35% * 65,000 g/mol = 227.5 g/mol

Next, convert the mass of iron to the number of iron atoms by dividing by the atomic mass of iron:

1 iron atom = 55.845 g/mol

number of iron atoms = 227.5 g/mol / 55.845 g/mol/atom = 4.069 x [tex]10^{23}[/tex]iron atoms/mol

So there are approximately 4.069 x [tex]10^{23}[/tex] iron atoms in a single hemoglobin molecule.

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The 2,4-hexadienol and the maleic anhydride were readily observed using the uv light, the product was only clearly observed after iodine staining as they were unsaturated products.

The 2,4-hexadienol and the maleic anhydride were readily observed using the uv light, the product was only clearly observed after iodine staining because as we know when product comes in contact with the iodine vapors, it reacts with the compounds and forms yellowish brown spots which can be easily seen.

Due to iodine, it forms complex with many organic compounds. we know iodine has affinity for both unsaturated and aromatic compounds, therefore both of them given compounds are unsaturated organic compounds along with the product.

Thats why, we know that when the 2,4-hexadienol and the maleic anhydride were readily observed using the uv light, the product was only clearly observed after iodine staining as they were unsaturated products.

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According to the kinetic energy theory, collisions between molecules in a gas called elastic collision.

According to the kinetic theory of gases, collisions between molecules in a gas are called elastic collisions. In an elastic collision, the total kinetic energy of the colliding molecules is conserved. This means that the total energy of the system before and after the collision is the same. However, the kinetic energy may be redistributed between the colliding molecules, which can result in a change in their velocities and directions of motion.

Elastic collisions are an important concept in the kinetic theory of gases because they help to explain the macroscopic properties of gases, such as pressure, temperature, and volume, in terms of the behavior of their constituent molecules. For example, when gas molecules collide with the walls of a container, they exert a force that contributes to the pressure of the gas. The rate and frequency of these collisions are affected by the temperature and volume of the gas. The kinetic theory of gases provides a theoretical framework for understanding the relationship between these macroscopic properties and the microscopic behavior of gas molecules.

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If a demineralizer bed reaches a point where the demineralizer resin can no longer hold any more ions, the bed is said to be exhausted.

Demineralizer beds are used in water treatment to remove dissolved minerals (e.g., calcium, magnesium, and iron) and other ionic impurities from water. Demineralizer beds typically consist of ions exchange resin beads that are packed into a column or tank. The resin beads have an affinity for certain ions (e.g., calcium and magnesium) and will exchange these ions for other ions (e.g., hydrogen or sodium) in the water. Over time, as the resin beads become saturated with exchanged ions, the capacity of the bed to remove further ions decreases.

When the resin becomes saturated and can no longer remove any more ions, the bed is considered to be exhausted. At this point, the resin must be regenerated or replaced in order to restore the demineralizer bed to its original capacity. The regeneration process involves washing the bed with a solution that displaces the exchanged ions and replaces them with fresh exchange ions. Once the regeneration process is complete, the demineralizer bed is ready to be used again to remove ions from the water.

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[Ar]4s24p5  is the electron configuration for Br and Y in noble-gas notation on Using  the periodic table.

Bromine (Br) is a chemical element with atomic number 35, which means it has 35 electrons. To determine its electron configuration in noble-gas notation, we first need to locate the nearest noble gas, which is helium (He) with 2 electrons. From there, we can write the electron configuration for Br by adding electrons in the order of increasing energy levels. Starting from the He configuration, we add the electrons for the next energy levels: 2s2, 2p6, 3s2, and 3p6. Finally, we add the remaining 5 electrons in the 4th energy level, giving us the noble-gas notation [Ar]4s24p5 for Br. Yttrium (Y), on the other hand, is a metal element with atomic number 39, which means it has 39 electrons. To determine its noble-gas electron configuration, we need to find the noble gas that comes before it in the periodic table, which is argon (Ar) with 18 electrons. Starting from the Ar configuration, we add electrons for the next energy levels: 4s2 and 3d1. This gives us the noble-gas notation [Kr]5s24d1 for Y. Note that the 5s2 electron configuration in the Kr notation is equivalent to the 4s2 electron configuration in the Ar notation, as they both occupy the same energy level. Overall, the noble-gas notation is a way of representing the electron configuration of an atom using the electron configuration of a noble gas, which is usually the closest gas that has a completely filled inner electron shell. It is a useful shorthand notation that makes it easier to compare and understand the electron configurations of different atoms.

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