What is Niels Bohr’s Theory

Answers

Answer 1
In 1913, Niels Bohr proposed a theory for the hydrogen atom, based on quantum theory that some physical quantities only take discrete values. Electrons move around a nucleus, but only in prescribed orbits, and If electrons jump to a lower-energy orbit, the difference is sent out as radiation.

Related Questions

A thermite reaction realeses large amounts of heat and light resulting in the melting of the iron metal

Answers

Answer:

1. Fe₂O₃ : Al = 1 : 2

2. Fe₂O₃ : Al₂O₃ = 1 : 1

3. Fe₂O₃ : Fe = 1 : 2

Note: The question is incomplete. The complete question is given below :

A thermite reaction releases large amounts of heat and light, resulting in the melting of the iron metal that forms during the reaction. The balanced chemical equation is given below: Fe₂O₃(s) + 2Al(s) ---> Al₂O₃(s) + 2Fe(l) Determine the correct mole ratios for the following substances, based on this chemical equation.

Explanation:

A thermite reaction is a highly exothermic reaction that occurs between a mixture of powdered aluminium and iron (iii) oxide.

The reaction is a redox reaction which produces aluminium oxide and metallic iron.

The heat given out in the reaction melts the iron formed. It is used to join railway tracks or cracked machine parts. The molten iron runs down between the tracks and welds them together.

The balanced equation of the reaction is given below :

Fe₂O₃(s) + 2Al(s) ---> Al₂O₃(s) + 2Fe(l) + Heat

The mole ratio of the reactant and products are as follows:

1. 1 mole of Iron (iii) oxide and 2 moles of aluminium are combined

Fe₂O₃ : Al = 1 : 2

2. 1 mole of aluminium oxide is produced from 1 mole of iron (iii) oxide

Fe₂O₃ : Al₂O₃ = 1 : 1

3. 2 moles of of iron are produced from 1 mole of iron (iii) oxide

Fe₂O₃ : Fe = 1 : 2

HELP ME !!!!!!!
How much kinetic energy does an 8 Kg bowling ball have when it is thrown at 9 m/s down the alley?

A. 324 J

B. 36 J

C.705.6 J

D.324 energies

Answers

Answer:

A. 324 J

Explanation:

what gives bases their properties?

Answers

Bases are iconic compounds that produce negative hydroxide ions (OH-) when dissolved in water. Bases taste bitter, feel slippery, and conduct electricity when dissolved in water.... Bases turn red litmus paper blue. The strength of bases is measured on the pH scale.

Durante una determinación de acidez en una muestra contaminada, agregas como indicador fenolftaleina y torno a violeta. ¿Qué sustancia utilizarías para titular NaOH o HCI? Y ¿Por qué?

Answers

Answer:

HCl, ya que la sustancia es una base que se debe titular con un ácido.

Explanation:

¡Hola!

En este caso, teniendo en cuenta la descripción inicial de la sustancia, la cual se torna violeta cuando se le agrega la fenolftaleína, es posible inderir que esta sustancia es una base con pH básico. Ahora bien, en torno a la especificación de un proceso de titulación, es claro que dicha base debe ser titulada con un ácido, y este caso, con HCl, ácido chlorhídrico, con el fin the alcanzar el punto de equivalencia.

¡Saludos!

Calculate the equilibrium constant of the reaction below if the pressures are 1.0atm, 2.0 atm, and 1.0 atm respectively. PCl3 + Cl2 <--> PCl5

Answers

Answer:

K = 0.5

Explanation:

Based on the reaction:

PCl₃ + Cl₂ ⇄ PCl₅

The equilibrium constant, K, is defined as:

K = P PCl₅ / P PCl₃ * P Cl₂

Where P represent the pressure at the equilibrium for each one of the gases involved in the equilibrium.

As:

P PCl₅ = 1.0atm

P PCl₃ = 1.0atm

P Cl₂ = 2.0atm

K = 1.0atm / 1.0atm * 2.0atm

K = 0.5

A hydrocarbon substituent is called an

Answers

It’s called An alkyl group.
Aliphatic hydrocarbons are divided into three main groups according to the types of bonds they contain: alkanes, alkenes, and alkynes. Alkanes have only single bonds, alkenes contain a carbon-carbon double bond, and alkynes contain a carbon-carbon triple bond.

which of the following is an example of a synthesis reaction

Answers

Answer: S+O2> SO2

Explanation:

2) __H,PO, +
KOH →
K PO + H2O
a- Balance the equation
b- Find the limiting reactant when 2.5 g H,PO, react with 4 g of KOH
C- What is the excess reactant?
d- How much of the excess reactant remained after reaction proceeded?

Answers

Explanation:

a.H2PO4 + 2KOH = K2PO4 + 2H2O

b. H2PO4 _ 2KOH

1(2) + 31 + 16(4) _ 2(23) + 2(16) + 2(1)

2 + 31 + 64 _ 46 + 32 + 2

97 _ 80

no of moles of H2PO4 = 2.5 ÷ 97

= 0.026mol

no of moles of 2KOH = 4 ÷ 80

= 0.05mol

2KOH is the limiting reactant

c. H2PO4 is the excess reactant

d. 1 mole H2PO4 weighs 2.5g

0.026mol H2PO4 weighs g

(0.026 × 2.5)

H2PO4 weighed 0.065g after reaction

I need helpppp plsss

Answers

Answer: Blank 1: 6

Blank 2: 1

Blank 3: 7

Explanation:

According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation. Explanation: According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.

The balanced chemical equation will be:

[tex]6H_3BO_3\rightarrow H_4B_6O_{11}+7H_2O[/tex]

can someone help me with this! because it have no idea what i’m doing feel free to solve anyone of these. THANK YOU

Answers

Answer:

1. 250 J

2. 500000 J

3. 146250 J

4. 400 J

Explanation:

1. Determination of the energy of the ball.

Mass (m) = 5 Kg

Velocity (v) = 10 m/s

Energy (E) =?

E = ½mv²

E = ½ × 5 × 10²

E = 2.5 × 100

E = 250 J

2. Determination of the energy of the rock.

Mass (m) = 250 Kg

Height (h) = 200 m

Acceleration due to gravity (g) = 10 m/s²

Energy (E) =?

E = mgh

E = 250 × 10 × 200

E = 500000 J

3. Determination of the energy of the car.

Mass (m) = 1300 Kg

Velocity (v) = 15 m/s

Energy (E) =?

E = ½mv²

E = ½ × 1300 × 15²

E = 650 × 225

E = 146250 J

4. Determination of the energy of the bullet.

Mass (m) = 0.005 Kg

Velocity (v) = 400 m/s

Energy (E) =?

E = ½mv²

E = ½ × 0.005 × 400²

E = 0.0025 × 160000

E = 400 J

Answer:

Sorry for the late answer but

Number 1 is 250 J

Number 2 is 500000 J

Number 3 is 146250 J

Number 4 is 400 J

Explanation:

Please help please help me ASAP

Answers

Answer:

0.3?

Explanation:

what are two places that producers can get energy?

Answers

Answer:

The Food Chain: The answer has to do with trophic levels. As you probably know, the organisms at the base of the food chain are photosynthetic; plants on land and phytoplankton (algae) in the oceans. These organisms are called the producers, and they get their energy directly from sunlight and inorganic nutrients.

Explanation:

Brainliest?

Zoe, a nutritionist, is giving a presentation about childhood obesity to a group of teachers. She ends her speech with this statement: "We can do better. We must eat healthier and exercise. Will you join me?”

This is an effective conclusion because it

leaves a lasting impression for the audience.
gives supporting details for the main idea.
establishes the main idea of the presentation.
gets the audience interested to hear more.

Also The answer is A) leaves a lasting impression for the audience.
Thx me latter!

Answers

Answer:

A

Explanation:

The statement made by Zoe as follows "We can do better. We must eat healthier and exercise. Will you join me?” is an effective conclusion because it leaves a lasting impression for the audience.

How is an effective conclusion made?

Public speakers are those who speak to a group of people in a structured manner.

However, asides presenting a spectacular body message, the conclusion must leave a lasting impression on the audience to enable them practice what was presented.

According to this question, Zoe made a conclusive statement as follows: "We can do better. We must eat healthier and exercise. Will you join me?”. This statement is an effective conclusion because it makes a lasting impression.

Learn more about public speaking at: https://brainly.com/question/10454613

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Your teacher asked you to identify the stage of mitosis of a specimen under the microscope. You observed that instead of a typical round cell shape, the cell has a narrow middle part which almost separates into two bulging ends and which looks like the number 8. What stage is the cell in? *

A. Interphase
B. Anaphase
C. Metaphase
D. Cytokinesis

Answers

Answer:

D. Cytokinesis

Explanation:

Mitosis is the cell division that involves the synthesis of two genetically identical daughter cells. Mitotic division occurs in stages namely: prophase, metaphase, anaphase and telophase. Following this four processes is another called CYTOKINESIS

Cytokinesis, which occurs after nuclear division, is the division of the cytoplasm. According to this question, the observation made when viewing the specimen was that "the cell has a narrow middle part which almost separates into two bulging ends and which looks like the number 8". This described the process of CYTOKINESIS in plant cell specifically.

where does energy come from? newsela

Answers

Answer:

All of our energy comes from the sun.

Explanation:

The sun sends out huge amounts of energy through its rays every day. Without the sun, life on earth would not exist, since our planet would be totally frozen.

When glucose is fermented, ethanol is formed together with ………………….

Answers

Answer:

carbon dioxide and oxygen

Methane undergoes combustion. Which products form?


 
CO2, H2O, and O2

 
C and H2O

 
CO2 and H2O

 
CO2 and H​

Answers

When methane undergoes combustion the carbon dioxide (CO₂) and water (H₂O) is formed. Therefore, option C is correct.

What do you mean by combustion ?

A chemical reaction between two or more substances, usually involving oxygen, that produces heat and light in the form of a flame is called as combustion. The reaction is as follows:

CH4(g) + 2O₂(g) → CO₂(g) + 2H₂O

Methane burns in the presence of enough oxygen to produce carbon dioxide (CO₂) and water (H₂O). When it is burned, it produces a large amount of heat, making it an excellent fuel source.

Thus, option C is correct.

To learn more about the combustion, follow the link;

https://brainly.com/question/15117038

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CH4+202>CO2+2H2O ; How many grams of water are produced from 30.0g of oxygen? PLS HELP AND SHOW WORK!!!!

Answers

I was taught how to do it this way and trust me it is way easier than doing the stuff with fractions. I’ll upload a photo on how to do it

How many atoms of gallium are there in a sample of gallium that has a mass of 1.34g?

Answers

Answer:

Explanation:

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Which salt is most soluble at 90C?

Answers

Explanation:

sodium nitrate is most soluble at 90C.

Solubility is the ability to get dissolved. The salt of sodium is the most soluble salt at 90 degrees.

What is solubility?

Solubility is the compound's or substance's ability to get dissolved in the solvent for the formation of the solution. It depends on several factors like hydration energy, temperature, pressure, and lattice energy.

The size of sodium is small, it has less lattice energy compared to the hydration energy and can get readily dissolved as it can create a sphere around other ions to form the solution.

Therefore, sodium salt is the most soluble at 90 degrees celsius.

Learn more about solubility here:

https://brainly.com/question/15596863

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PLEASE HELP ASAP A gardener plants a new kind of plant that will attract more helpful insects to his garden. Suddenly, the gardener notices a significant increase in the number of spider webs in the garden. Why has most likely occurred in this situation?

The carrying capacity of the environment has changed.

The limiting factor for spiders has increased in amount.

The carrying capacity of the environment has not changed.

The limiting factor for spiders has decreased in amount.

Answers

Answer:

The carrying capacity has changed

Explanation:

By adding in the help bugs, the gardener increased the amount of food available for the predators who eat the help bugs, these are the spiders.

The enviroment for spiders now has more food, and can carry more spiders in it.

When a substance was dissolved in water, the temperature of the water increased. This process is described as
A.
endothermic with the release of energy
B.
endothermic with the absorption of energy
C.
exothermic with the release of energy
D
exothermic with the absorption of energy

Answers

The correct answer will be A

Answer: a,

endothermic with the release of energy

Plz help I need help plz ASAP

Answers

6:c

7: might be ice but im not really sure, hope you do well.

Explanation:

What charge would an ion have if it had more electrons than protong?

A. It would be neutral, since electrons would be outside the nucleus.
B. It would have a net positive charge.
C. It would have no charge.
D. It would have a net negative charge.

Answers

Answer:

D. It would have a net negative charge

Explanation:

In an atom, there are electrons, protons and neutrons collectively called SUBATOMIC PARTICLES. The charge of an atom is determined by the number of electrons and protons in that atom. A neutral or uncharged atom possess the same number of electrons and protons.

The charge can thus be calculated as follows:

Charge of atom = no. of protons - no. of electrons.

Hence, when the number of electrons in an atom is higher than that of the protons, it means that the atom has gained negatively charged electrons, making that atom have a net negative charge. For example, In an atom that contains 10 protons and 11 electrons, the charge of that atom will be (10 - 11) = -1. The net charge of that atom will be -1, which is NEGATIVE.

A larger balloon has 2.5 l of nitrogen gas at 298 k . If the temperature is increased to 333 k , what will be the new volume of balloon filled with nitrogen

Answers

Answer: The new volume of baloon filled with nitrogen is 2.8 L

Explanation:

To calculate the final volume of the system, we use the equation given by Charles' Law. This law states that volume of the gas is directly proportional to the temperature of the gas at constant pressure.

Mathematically,

[tex]\frac{V_1}{T_1}=\frac{V_2}{T_2}[/tex]

where,

[tex]V_1\text{ and }T_1[/tex] are the initial volume and temperature of the gas.

[tex]V_2\text{ and }T_2[/tex] are the final volume and temperature of the gas.

We are given:

[tex]V_1=2.5L\\T_1=298K\\V_2=?\\T_2=333K[/tex]

Putting values in above equation, we get:

[tex]\frac{2.5}{298}=\frac{V_2}{333}\\\\V_2=2.8L[/tex]

Thus the new volume of baloon filled with nitrogen is 2.8 L

8. A transform boundary, where one tectonic plate slides past another, is likely to result in
which of the following?
A. Frequent earthquakes
B. Rift valley formations
C. Intense weathering
D. Mountain building
9. A rising hot air balloon is acted on by a force pulling it upward and by the force of gravity
Nonton's law of inertia what will happen to the balloon

Answers

Answer:      A. Frequent earthquakes

Explanation:

BRAINIEST!! how do i balance As+H2=AsH3 step by step will give brainiest only to people who do step by step

Answers

Answer:

1. As+H2=AsH3

2. draw a line under the problem with this:

A = 1            | A = 1

H = 2           | H = 3

3. We need everything to be equal (2x3 to get 6 then count the As on the product side to get the 2, then add 2 A on the reactant side):  

A = 2            | A = 2

H = 6           | H = 6

4. 2As + 3H2 = 2AsH3

hope this helps

How much water is needed to dissolve 30g or Pb(NO3)2 at 40.0C answer the question? NO BOTS ALLOWED

Answers

Answer:

10 must be added

Explanation:

Insects often get stuck in the sap of ancient trees. The sap along with the insect inside harden forming a fossil. What kind of fossil is this?

Cast
Crystallization
Mold
Trace

Answers

Crystallization

This is because insects that usually get stuck in sap tend to harden or crystallize, so they cannot get out. That is why it is a crystallization.

Which of these statements is true of plant cells?
O They are prokaryotic.
O They have no cell membranes.
They can make their own nutrients.
O They work independently of one another.

Answers

C. They can make their own nutrients
The answer would be C
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