why was the bohr model replaced

Answers

Answer 1

To solve this we must be knowing each and every concept related to atom. Therefore, Bohr's model was abandoned since it lacked explanatory, descriptive, and predictive ability.

What is atom?

Atom is the smallest particle of any element, molecule or compound. Atom can not be further divided. Atoms contains nucleus in its center and electron that revolve around the atom in fixed orbit.

In the nucleus, proton and neutron are present. Electron has -1 charge while proton has +1 charge. Neutron is neutral that is it has no charge. Bohr's model was abandoned in favor of the quantum mechanical model since it lacked explanatory, descriptive, and predictive ability.

Therefore, Bohr's model was abandoned since it lacked explanatory, descriptive, and predictive ability.

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Related Questions

Nitric acid has the formula HNO3. If there are 3. 55x10^23 atoms of O in the sample, how many moles of nitric acid are there?​

Answers

Nitric acid has the formula HNO₃. If there are 3. 55x10²³ atoms of O in the sample, the number of moles of nitric acid is 0.589moles.

Define mole.

How many moles of a substance are present in a reaction is determined by comparing its mass to the mass of one mole. One mole, or Avogadro's number, is equal to the sample mass divided by the molar mass, or 6.023×10²³ moles. You can calculate the total number of atoms or molecules in a sample by dividing the number of moles by the Avogadro constant. The equation is: Number of Molecules=Atoms or Molecules /6.022×10²³.

1 mole oxygen atom contains 6.02×10²³ atoms

how many moles of oxygen contains 3.55x 10²³atoms

Moles of nitric acid = 3.55x 10²³atoms/6.02 ×10²³atoms

Moles of nitric acid = 0.589moles.

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The following data was collected when a reaction was performed experimentally in the laboratory.


Reaction Data:

Reactants:

Fe2O3 (3 moles)

Al (5 moles)

Products:

Al2O3 (?)

Fe (?)

Determine the maximum amount of Fe that was produced during the experiment. Explain how you determined this amount.


Please be thorough. I am in agony at this question and I need the most help I can get. Thanks

Answers

According to the data collected during the experimental reaction in the laboratory, and the balanced equation of the reaction, 5 moles of iron (Fe) and 2.5 moles of aluminum oxide (Fe2O3) were produced.

Determination of the maximum amount of Fe that was produced during the experiment.

Balanced equation of the reaction

Fe2O3 + 2Al → 2Fe + Al2O3

Limit reagent determination

If 1 mole of Fe2O3 is combined with 2 moles of Al

So 3 moles of Fe2O3 combine with x moles of Al

X moles of Al = 3 moles Fe2O3 x 2 moles Al / 1 mole Fe2O3 = 6 moles

Limiting reagent: Al, because there are only 5 moles available

Determination of the amount of iron produced

If 2 moles of Al produce 2 moles of Fe

So 5 moles of Al produce x moles of Fe

X moles of Fe = 5 moles of Al x 2 moles of Fe / 2 moles of Al = 5 moles

Determination of the amount of aluminum oxide produced

If 2 moles of Al produce 1 mole of Fe2O3

So 5 moles of Al produce x moles of Fe2O3

X moles of Fe = 5 moles of Al x 1 mole of Fe2O3 / 2 moles of Al = 2.5 moles

Explanation about the procedures used to determine the amount of iron

By establishing the balanced equation of the reaction and the stoichiometric relationships, the amount of limit reagent is first determined and with this data, the moles of products are later determined.

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Which one of the following statements is not correct about MSDS?


Select one:


a.

It does not contain information on physical and chemical properties of the material, potential hazards of the material and how to work safely with these materials.



b.

It provides single reference for all information about hazardous chemicals.



c.

Material Safety Data sheet forms the important elements of effective Chemical Hazards Communication System.



d.

It is a document prepared by the manufacturers/suppliers of the chemical

Answers

Option B. It provides a single reference for all information about hazardous chemicals.

MSDS does not provide a single reference for all information about hazardous chemicals, but it does provide information on physical and chemical properties, potential hazards, and safe work practices.

Understanding the Role of MSDS in Chemical Hazard Communication

The Material Safety Data Sheet (MSDS) is a document prepared by the manufacturer or supplier of a hazardous chemical which provides information about the physical and chemical properties of the hazardous chemical, potential hazards associated with it, and how to work safely with it. The MSDS is an important element of an effective chemical hazard communication system as it provides information on how to identify and protect against potential health hazards, proper storage and handling procedures, and proper disposal methods.

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In an experiment, potassium chlorate decomposed according to the following chemical equation.


2 KClO3 → 2 KCl + 3 O2


If the mass of potassium chlorate was 240 grams, what is the mass of oxygen gas formed?

Answer Choices:

A)

94. 03g

B)

1378g

C)

41. 8g

D)

612. 5g

Answers

Grams have been employed to estimate the mass of decomposition. Option C is correct, so.

The chemical response is as follows:

Every mole of must be broken to generate one mole of KCl.

180 kilograms of KCl was produced.

KCl produced in moles =

Produced moles of KCl equals moles.

Degradation of the same material is necessary for the creation of moles of KCl.

Therefore, the moles of the must be decomposed = moles.

Decomposition of mass equals moles of molecular weight

122.2 grammes of moles must be degraded from the mass.

Has to be decomposed for the production of 2 moles of KCl =

kilos.

Thus, kilograms has supplied the mass of decomposition. Option C is correct, however.

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The electron-domain geometry of the AsF6- ion is octahedral. The hybrid orbitals used by the As atom for bonding are ________ orbitals.

Answers

The AsF6- ion has an octahedral electron-domain shape. Sp3d2 orbitals are the hybrid orbitals that the As atom utilizes for bonding.

The octahedral geometry of AsF6-. All six fluorine atoms are sp3d2 hybrid orbitals with the central arsenic atom, and they all form 90° and 180° bond angles in an octahedral geometry. Arsenic(As), with atomic number 33, is the main atom in the AsF6-. Configuration of the formula As(33)=[Ar]3d104s24p3. As a result, As' valence shell contains five electrons. It can therefore create five single bonds with a fluorine atom and one more single bond with a fluorine atom as a result of one negative charge. Consequently, there are six bond pairings in total.

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Students are challenged to design cold packs for treating injuries. To do this they must find a chemical reaction that absorbs heat energy. The ideal chemical reaction will reach a temperature in the range of 0C to 4C and maintain that temperature for a minimum of 20 minutes

Answers

Students as a chemical reaction that absorbs thermal energy for the design of cold packs for the treatment of injuries can combine manganese oxide (MnO2) with hydrogen peroxide (H2O2)

By controlling the amounts of the reactants they can control the temperature, keeping it between 0 °C and 4 °C for 20 minutes or more.

This type of chemical reaction is called endothermic, because energy is absorbed in the form of light or heat, causing the resulting products to have higher energy than the reactants.

Chemical reaction that absorbs thermal energy fpr cold compresses for the treatment of injuries

The most widely used endothermic chemical reaction in the treatment of injuries is the melting of ice, at least in warm environments, which occurs according to the following reaction:

H2O (s) + Energy ----- H2O (l)

Decomposition of manganese oxide absorbs thermal energy

The effect of an endothermic reaction is absorbs heat energy and in the case of manganese oxide the following decomposition occurs:

MnO2 (s) → MnO (s) + ½ O2 (g); ∆HR = 134kJ

Students can design cold packs for treating injuries with manganese dioxide bcause it breaks down into two products, manganese oxide and oxygen, making the enthalpy greater than zero (∆HR > 0).

MnO2 is a solid between gray and black in color and is present in minerals such as pyrolusite and nsutite, when combined with hydrogen peroxide it acts as a catalyst so that it accelerates chemical reaction

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A sample of gas has a pressure of 3.4 atm at 300 K in a container with a fixed volume. What will be the pressure (in atm) of this same sample of gas if the temperature is changed to 402 K

Answers

If the temperature is raised to 402 K, the pressure (in atm) of this given sample of gas will be 4.5.

Given,

Pressure P1 = 3.4 atm

Temperature T1 = 300 K

       ⇒            T2 = 402 K

   ⇒                P2 = ?

    ⇒          P1/T1 = P2/T2

 ⇒         3.4/300 = P2/402

    ⇒              P2 = 4.5

   ⇒     Pressure = 4.5 atm

An atmosphere (atm) is a measuring unit that corresponds to the average air sea level pressure at 15 degrees Celsius (59 degrees Fahrenheit). One atmosphere consists of 1,013 millibars of pressure, or 760 millimetres (29.92 inches) of mercury.

Pressure is defined as the force exerted by one material on another per unit area. The force also that gas exerts on the container limits is defined as gas pressure. Gas molecules travel at random over the specified volume. They clash with the surface as well as each other during this movement.

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A 35.2-mL, 1.66 M KMnO 4 solution is mixed with 16.7 mL of 0.892 M KMnO 4 solution. Calculate the concentration of the fi nal solution.

Answers

The concentration of the final solution is 1.41[tex]\frac{mol}{L}[/tex].

Now, first calculate the number of moles of first solution:

[tex]M_{1} =\frac{no. of moles of solution}{total volume of solution}[/tex]

no. of moles we have to find

total volume is 0.0352L and molarity of solution is 1.66M

The total number of moles of solute present in a given solution per litre is known as its molarity. In contrast to mass, which varies as the system's physical circumstances vary, the volume of a solution changes as a function of changes in the system's physical qualities, such as pressure and temperature. This has an impact on the molality of the solution. The symbol M, sometimes known as a molar, denotes molarity.

[tex]1.66=\frac{n}{0.0352}[/tex]

on solving we get,

n=0.0584 mol

Now, find the number of moles of second solution by the same formula used to find the moles of first solution,

molarity of second solution is 0.892M and total volume is 0.0167L

Now, put the values in the formula,

[tex]0.892=\frac{m}{0.0167}[/tex]

On solving we get,

m=0.0149 mol

and to find the concentration of new solution number of moles is equal to the sum of moles of first solution and second solution.

x=m+n

x=0.0584+0.0149

x=0.0733 mol

Now, molar concentration is,

[tex]M=\frac{x}{V}[/tex]

[tex]M=\frac{0.0733}{0.352+0.0167}[/tex]

On solving we get,

M=1.41[tex]\frac{mol}{L}[/tex]

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Shown below is the phase diagram for a typical liquid mixture of two components, A and B. a What is the significance of the horizontal line between points X and Y? O The length of the line XY corresponds to the difference in boiling point of components A and B. O A boiling liquid with composition X will produce vapor with composition Y. O The point X gives the vapor composition of the less volatile component and Y gives the vapor composition of the more volatile component. The line gives the difference. O A boiling liquid with composition Y will produce a vapor with composition X. b Using the phase diagram, determine the molar composition of the vapor in equilibrium with a boiling liquid that has a composition of 40% A and 60.% B. Percentage vapor composition A= 10 % Percentage vapor composition B 90 % What is the boiling point of this liquid? Boiling point 100 °C

Answers

The line between points X and Y represents the difference in boiling points of components A and B. A boiling liquid with a composition of 40% A and 60% B will produce a vapor with a composition of 10% A and 90% B, and have a boiling point of 100°C.

The significance of the horizontal line between points X and Y on the phase diagram is that it represents the difference in boiling points of components A and B. This line indicates the point at which the vapor and liquid phases are in equilibrium. On the diagram, point X gives the vapor composition of the less volatile component, while point Y gives the vapor composition of the more volatile component.

By looking at the phase diagram, we can determine the molar composition of the vapor in equilibrium with a boiling liquid that has a composition of 40% A and 60% B. The vapor composition of the less volatile component (X) is 10%, while the vapor composition of the more volatile component (Y) is 90%. The boiling point of this liquid is 100°C.

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Draw plausible electron dot structures for the following substances. Each substance contains only single covalent bonds. A. I2 B. OF2 C.H2S D.NI3.

Answers

The plausible electron dot structures of I₂, OF₂, H₂S, NI₃ substances are attached below.

How is an electron dot structured?

Lewis dot structures, also known as electron dot structures, are diagrams that show how atoms in a molecule are chemically bonded to one another. They also show how many lone pairs there are in total among all the atoms that make up the molecule.

An electron configuration writing guide. The shell number (n) comes first in the symbols used to represent the electron configuration, followed by the type of orbital and, finally, a superscript that represents the number of electrons in the orbital. Examples include As you can see from the periodic table, oxygen has 8 electrons.

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The molar mass of bismuth (\ce{Bi}BiB, i) is \pu{208. 98 g/mol}208. 98 g/mol208, point, 98, space, g, slash, m, o, l. Calculate the mass in grams of a sample of \ce{Bi}BiB, i containing \pu{7. 35x10^23}7. 35×10 23 7, point, 35, times, 10, start superscript, 23, end superscript atoms

Answers

The mass in grams of a sample of Bi with 7.35 1023 atoms should be 255 grams.

What does molar mass in chemistry refer to?

A substance's mass is measured in grams per mole, or molar mass. The molar mass of a substance can be determined, as demonstrated in this video, by adding the molar masses of the substance's constituent atoms. The substance's molar mass can then be used to determine the number of moles in the substance and converted to mass.

The molar mass of Bi is 208.98 g/mol.

1 mole Bi = 208.98 g/mol = 6.023×10²³ no of atoms

So, the mass in grams should be

mass = ( 208.98 g/mol ×7.35 × 10²³) ÷ (6.023×10²³)

mass = 255 grams.

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Petroleum is a fossil fuel containing many different carbon compounds. If the carbon atoms in petroleum have been in the ground for 100 million years, what fraction of the initial 14C atoms is still there

Answers

Thus, Option (C) Glucose has a maximum of 72 C-atoms per gram. The components of fossil fuels are decaying plants and animals.

These fuels may be burned to provide energy and can be found in the crust of the Earth. An example of a fossil fuel is coal, as well as oil and natural gas. Due to the hydrocarbons and other carbon-based compounds they contain, fossil fuels are valuable as energy sources. Any of a class of organic molecules made solely of carbon and hydrogen are known as hydrocarbons. The hydrogen atoms adhere to the carbon atoms, which serve as the "skeleton" or framework. Because they were generated from the petrified, buried remains of plants and animals that once lived millions of years ago, coal, crude oil, and natural gas are all referred to as fossil fuels.

The complete question is- Petroleum is a fossil fuel containing many different carbon compounds. If the carbon atoms in petroleum have been in the ground for 875 million years, what fraction of the initial 14C atoms is still there?

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Why the properties of elements are repeated after 2 8 18 and 32 elements?

Answers

The properties of the elements are repeated after 2 8 18 and 32 elements because these are the maximum number of the electrons that the four shells contains.

The electronic configuration of the elements in the periodic table are repeated because the maximum number of the electrons that the four shells can have are 2 8 18 and 32. the name of the four shells are K , L, M, N. The electronic configuration of the elements are repeated and due to this the properties of the elements are repeated.

Thus, the properties of the elements are increases because the electronic configuration are repeated in the periodic table.

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Classify the following alcohols as primary secondary and tertiary alcohols​

Answers

Following is the list of primary secondary and tertiary alcohols.

Alcohols are chemical compounds made composed of an alkyl or aryl group and a hydroxyl group (ROH). A fundamental alcohol is a hydroxyl carbon with just one R group. If it contains two R groups, it is a secondary alcohol, and if it has three R groups, it is a tertiary alcohol.

Look at the carbon bonded to OH to identify whether an alcohol is primary, secondary, or tertiary. The alcohol is primary, secondary, or tertiary depending on how many other carbons are connected to that carbon. It is methanol if there are three hydrogens and no carbons, which is a rare combination.

For the given formulas, following are different types of alcohols -

a) Primary Alcohols

b) Tertiary Alcohol

c) Secondary Alcohol

d) Primary Alcohol

e) Primary Alcohol

f) secondary Alcohol

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Explain if the process of turning pennies into brass would work on other coins - like a quarter, nickel, or dime.

Answers

The process of turning pennies into brass simply has to do with dissolving the copper in the penny by a chemical process and this is then replaced with a brass alloy and this process could theoretically be applied to other coins.

What is a coin?

A coin is a tiny, flat, round piece of metal or plastic which is used as legal tender or a medium of exchange. It should be noted that they are mass-produced at a mint so as to facilitate trade, and their weight is standardized.

In order achieve various mechanical, electrical, and chemical properties, it should be noted that copper and zinc can be combined in different ratios in order to create the alloy known as brass.

The composition of other coins, such as quarters, nickels, and dimes, is different from pennies and would require different chemical processes to alter. Additionally, it is illegal to deface or alter U.S. coin currency, so it would not be legal to do this process on any other coin. In this case, it can be applied to other coins.

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Give the orbital configuration of the following elements using the s, p, d, f type representation. (Answer format is: 1se2

Answers

The orbital configuration of following elements is as follows: i) helium- 1 s² ii)nitrogen- 1 s² 2 s²  2 p³ iii)silicon-1 s² 2 s² 2 p⁶ 3 s² 3 p²

What are elements?

It is defined as a substance which cannot be broken down further into any other substance. Each element is made up of its own type of atom. Due to this reason all elements are different from one another.

Elements can be classified as metals and non-metals. Metals are shiny and conduct electricity and are all solids at room temperature except mercury. Non-metals do not conduct electricity and are mostly gases at room temperature except carbon and sulfur.

The number of protons in the nucleus is the defining property of an element and is related to the atomic number. All atoms with same atomic number are atoms of same element.

Here,

The orbital configuration of following elements is as follows: i) helium- 1 s² ii)nitrogen- 1 s² 2 s²  2 p³ iii)silicon-1 s² 2 s² 2 p⁶ 3 s² 3 p²

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Benzene (C6H6) burns in air to produce carbon dioxide and liquid water. How much heat is released per mole of benzene combusted? The standard enthalpy of formation of benzene is 49.04 kJ/mol

Answers

Benzene (C6H6) burns in air to produce carbon dioxide and liquid water.The heat released in KJ per gram of the compound reacted with oxygen is -41.83 KJ.

What is heat ?

Heat is the result of the movement of kinetic energy within a material or an item, or from an energy source to a material or an object. Radiation, conduction, and convection are the three mechanisms through which such energy can be transferred.

The movement of minuscule atoms, molecules, or ions in solids, liquids, and gases produces heat energy. From one thing to another, heat energy can be exchanged. Heat is the flow or transfer that occurs as a result of the temperature differential between two objects.

Reaction as follows;

2C6H6 + 15O2 → 12CO2 + 6H2O

2x49.04   2x10       12x-393.5  6x-285.8

= [ 12(-393.5 )+6(-285.8) ] - [ 2(49.04)+(2x10) ]

= - 6936.8 - 98

= - 6534.8 KJ/mole

Per gram of benzene

= ( -6534.8 KJ / 2 mole of C6H6) (1 mole of C6H6 / 78.108g )

= -41.83 KJ / mole

Thus, The heat released in KJ per gram of the compound reacted with oxygen is -41.83 KJ.

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What can help overcome a positive enthalpy of solution and allow a solid solute to dissolve in water

Answers

New ion-dipole or dipole-dipole attractions take effect if the solute is an ion or polar molecule on its own.

When things go well, they could release enough potential energy to partially offset the energy needed to integrate the solute into the structure. Ammonia dissolving in water is a striking illustration of this.  Solution's enthalpy. A solution is a uniform combination of two or more components that can exist in the solid, liquid, or gas phases. The amount of heat that is emitted or absorbed during the dissolving process is known as the enthalpy change of solution (at constant pressure).The solvent molecules begin to dissociate as a result. This process' enthalpy is referred to as. Since energy is needed to break the contact between the B molecules, this reaction, like the first, is always endothermic (). Let's try to picture what has transpired up to this point.

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In biology, a system is a collection of (blank)
(each made of multicellular tissues) that together perform a major function.

Answers

In biology, a system is a collection of organs (each made of multicellular tissues) that together perform a major function.

What is the organ about?

In biology, a system refers to a collection of organs that work together to perform a specific function or set of functions. Organs are structures made of multiple types of tissues that work together to perform a specific task.

These tasks can be related to maintaining homeostasis, such as the circulatory system which transports oxygen and nutrients throughout the body, or to a specific function, such as the reproductive system which is responsible for the production of offspring.

Therefore, Organs within a system are highly specialized and have specific functions, but they also work together in concert to achieve the overall function of the system. For example, the digestive system is made up of several organs including the mouth, esophagus, stomach, small intestine, and large intestine.

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Tungsten 188 decays by beta. Find the daughter product.
daughter product (mass.atomic/,element symbol);

Answers

By beta, tungsten 188 decays. The mechanism through which an insecure atomic structure is produced is known as radioactive decay.

How does radioactive decay work?

The process through which highly unstable molecular nucleus loses its energy through radiation is described as radioactive decay, also characterized as nuclear decay, radiography, radioactivity breakdown, or nuclear disintegration. A substance that has unstable nuclei is regarded as radioactive. For a large variety of human activities, radioactive decay is crucial.

What occurs when radioactive material decays?

Alpha, beta, and/or gamma rays are all types of ionizing radiation that are released when radioactive atoms decay. Because the energy is powerful enough to dislodge firmly coupled electrons from just an atom's orbit, it is known as ionizing radiation. As a result, the atom develops into a charged ion.

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Please help, would be greatly appreciated!

Answers

According to the stoichiometry of the given chemical equation 102.03 g of Al₂O₃ is formed from 54 g of aluminium.

What is stoichiometry?

It is the determination of proportions of elements or compounds in a chemical reaction. The related relations are based on law of conservation of mass and law of combining weights and volumes.

Stoichiometry is used in quantitative analysis for measuring concentrations of substances present in the sample. As per stoichiometry of the given chemical equation, 107.92 g aluminium gives 203.92 g Al₂O₃, thus 54 g aluminium will give 54×203.92/107.92=102.03 g.

Thus,  102.03 g of Al₂O₃ is formed from 54 g of aluminium.

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Outside city limits, the minimum distance for parking cars from a warning cross indicating a railroad crossing is 50 meters (165 feet).


a. True. B. False

Answers

The given statement is false - outside city limits, the minimum distance for parking cars from a warning cross indicating a railroad crossing is 50 meters (165 feet).

Which of the following must you keep a safe distance from when parking at a railroad crossing?

Within 100 feet of a railroad crossing, bridge, tunnel, or other potentially dangerous location.

To ensure the safety of drivers on the road, the relevant authorities have made a number of rules regarding parking cars and other vehicles.

The authorities have made regulations regarding car parking close to railroad crossing signs in consideration of public safety and potential conditions relating to traffic accidents.

Because trains follow a different route and are a different mode of transportation, sometimes they must cross over the sides of the road.

The maximum length for parking a car outside the city limits has been set at 50 meters in order to prevent accidents that might happen as a result of track failure or other technical issues.

The same limit for parking a car inside the city's boundaries, however, has been set to at least 10 meters, or roughly 33 feet, due to space restrictions.

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A 467. 8 ng sample of unknown radioactive substance was placed in storage and its mass measured periodically after 47 days the amount of radioactive substance had decreased 58. 48 ng how many half-lives of the non-radioactive substance have occurred

Answers

The amount of radioactive substance has decreased from 467.8 ng to 58.48 ng after 47 days, so 2.5 half-lives have occurred.

A radioactive isotope's half-life is the amount of time it takes for one half of the radioactive isotope to decay. A specific radioactive isotope's half-life is constant; it is unaffected by conditions and is independent of the initial amount of that isotope.

Half-life = 47/2.5 = 18.8 days

Decrease in Radioactive Substance = 467.8 - 58.48 = 409.32

Half-life amount = 409.32/2.5 = 163.728

Number of half-lives = 409.32/163.728 = 2.5

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Heat conservation is important for polar endotherms, thus they tend to be _________ so that they __________ their surface area to volume

Answers

Polar endotherms must save heat, hence they usually have a significant surface area to volume ratio. The capacity to maintain blood is what makes heat conservation unique.

Vasoconstriction keeps it in the centre by decreasing blood flow to the outside (also known as peripheral vasoconstriction). An endotherm is an organism that uses heat produced by its internal biological processes rather than nearly exclusively relying on ambient heat to keep its body at a metabolically advantageous temperature. In thermodynamics, heat is defined as a kind of energy that crosses a thermodynamic system's boundary due to a temperature differential across the barrier. Heat is not present in a thermodynamic system.

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dental cement, Zn3(PO4)2

Give only the names of the elements alphabetically, separating them with commas.

Answers

Zinc, phosphorus and oxygen are elements contained in dental cement (Zn₃(PO₄)).

Dental cements have a wide range of dental and orthodontic applications. Common uses include temporary tooth restoration, lining cavities to protect the pulp, sedation or isolation, and cementation of fixed prosthetic devices.

A cement-retained bridge is simply a dental device that is permanently fixed in the mouth to restore the mouse's function and aesthetics and to prevent many of the consequences of tooth loss that affect the immediate aftermath of losing natural teeth.

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What happens to molecules when they move faster?

Answers

When molecules move faster, they increase their kinetic energy.

What is Kinetic energy?

Kinetic energy is essentially the energy of motion. It is the type of energy that an object possesses as a result of its motion. It is commonly defined as the work required to accelerate a given mass body from rest to its stated velocity. Kinetic energy is directly related to the object's mass and the square of its velocity.

This increase in kinetic energy causes the molecules to vibrate more rapidly, resulting in an increase in temperature. As molecules move faster, they also collide with each other more frequently, leading to more chemical reactions.

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The poles of an electromagnet can even be reversed by reversing the flow of electricity true or false

Answers

By reversing the flow of electricity, the poles of an electromagnet may be reversed. As a result, the following statement is true.

An electromagnet is a magnet that uses electricity to operate. In contrast to a permanent magnet, the strength of an electromagnet may be readily altered by varying the amount of electric current flowing through it. By reversing the flow of electricity, the poles of an electromagnet can even be reversed.

An electromagnet is created when an electric current produces a magnetic field. The resulting magnetic field surrounds the original electric current, forming circles
When an electric current is passed through a wire, the magnetic field created can be concentrated within certain areas. This effect can be further strengthened by wrapping the wire around a stable core. Certain materials, such as ironnickel and cobalt, have atoms that act like tiny magnets. 
As the current flows around the core, increasing in intensity until all of the atoms are aligned, the magnetic field becomes stronger. At some point, however, this will happen and further increases in electric current will not affect the magnetization.

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Which of the following require(s) resonance structures to more accurately represent their electron arrangements

Answers

The correct representation about resonance structures is that The structure of the species cannot be correctly predicted by a single resonance structure and the only way resonance structures vary is in the way the electrons are arranged.

In valence bond theory, resonance is defined as a hybrid structure formed by combining a variety of contributing structure into a resonance hybrid. Because orbitals overlap, resonance happens. Pi bonds, created when two 2p orbitals overlap, are the building blocks of double bonds. These pi orbitals' electrons are delocalized since they will be dispersed across more than two atoms.

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Fictitious element X has an average atomic mass of 122. 131 u. Element X has two naturally occuring isotopes. The most abundant isotope has an isotopic mass of 121. 552 u and a relative abundance of 61. 35%. Calculate the isotopic mass of the least abundant isotope

Answers

The isotopic mass of the least abundant isotope will be 123.05 u.

Average atomic mass of X = 122.131 u

Assume most abundant isotope = Y and least abundant isotope = Z

Relative abundance (Y) = 61.35%

So,

Z = 100 - 61.35

Z = 38.65 %

Isotopic mass of Y= 121.552 u

Isotopic mass of Z = ?

To calculate the isotopic mass we use the following formula:

Average atomic mass = [(mass Y × percent abundance) + (mass Z × percent abundance)] / 100

put the values

122.131 = [(121.552 × 61.35) + (Z × 38.65)] / 100

12213.1 = (7457.22) + (Z × 38.65)

Z × 38.65 = 12213.1 - 7457.22

Z × 38.65 = 4755.88

Z = 4755.88 / 38.65

Z = 123.05

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I need to know the Lewis structure for

CCI4

H2O

O2

N2

PH3

Please and thank you.

Answers

Two solitary sigma bonds are visible in the Lewis structure between the hydrogen and oxygen atoms.

What is Lewis structure explain with example?

The octet rule is a theory that describes how atoms share electrons so that each atom has eight electrons in its outer shell. This idea is the foundation of a Lewis structure. An oxygen atom, as an illustration, has six electrons in its outer shell.

The entire molecule's electron density is concentrated only around the core C in the CCl4 Lewis structure. Two nitrogen atoms are connected by a triple bond in the N2 Lewis structure.

In the reaction described above, PH3 is acting as a Lewis base because of the single electron on the P atom.

A double bond exists between two oxygen atoms in the Lewis structure of O2. Oxygen atoms must form two bonds in order to comply with the octet rule. The oxygen (red) and hydrogen (white) atoms are held together by powerful connections known as covalent bonds.

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