As a result, 6.022 x 10 23 molecules of water weigh 18.02 g. A mole of sodium chloride (6.02 x 1023 formulas) weighs 58.44 g.
A substance's mole is equivalent to 6.022 x 1023 of that material (such as atoms, molecules, or ions). One mole, or 6.022 x 1023 molecules, is equal to one gram's worth of any given substance's molecular mass. Thus, a mole of oxygen (O2) weighs 32 kilos and has a molecular mass of 6.022 1023.
12 grams of pure carbon-12 weigh exactly one mole, or 6.022 x 1023 atoms, making one mole equivalent to 12 grams of pure carbon-12. • Avogadro's Number refers to the quantity of particles contained in one mole (6.0221421x1023).
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What is the relative rate of diffusion of CH4 and NO2?
The ratio of effusion rates of Sulphur dioxide and methane is 0.5
To calculate the rate of diffusion of gas, we use Graham's Law.
This law states that the rate of effusion or diffusion of gas is inversely proportional to the square root of the molar mass of the gas. The equation given by this law follows the equation:
Rate of Diffusion ∝ 1 ÷ √molar mass of the gas
We are given:
Molar mass of Sulphur dioxide = 64.066 g/mol
Molar mass of methane = 16.04 g/mol
By taking their ratio, we get:
Rate of SO₂ ÷ Rate of CH₄ = √MCH₄ ÷ √MSO₂
Rate of SO₂ ÷ Rate of CH₄ = √16.04 ÷ √64.066
Rate of SO₂ ÷ Rate of CH₄ = 0.5
Hence, the ratio of rate of effusion of Sulphur dioxide and methane will be 0.5
How can you deduce if a compound is optically active or not ?
Answer:
look for evidence that the molecules are chiral.
Explanation:
The instrument with which optically active compounds are studied is a polarimeter, shown in the figure below. Imagine a horizontal line that passes through the zero of a coordinate system.
Why are the elements in Groups 1 and 17 so reactive?
Fluorine as well as chlorine are among the substances in group 17. Alkali metals as well as hydrogen are both part of group 1 on the periodic table.
Group 1 elements were extremely reactive due to the fact that they only contain one valence electron. As just a result, atoms were only ever combined with some other elements present in nature.
Due to their size as well as low ionisation enthalpy, alkali metals were extremely reactive metals. Moving lower in the group causes them to become more reactive. Reactivity to air: These metals discolor when exposed to dry air because oxides create, which then react with moisture to generate hydroxides.
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Since carbon-14 decays at a steady rate, it is a reliable method to determine the age of rock samples. True False
The aforementioned claim is TRUE; as carbon-14 degrades steadily, it can be used to accurately estimate the age of rock samples.
Comment on carbon-14.The radioactive isotope of carbon 14 (14C) decays at a constant, well-known pace. Scientists can ascertain how long ago an organic substance died by calculating the quantity of 14C present in a sample of the material, such as bone or wood. This process, known as radiocarbon dating, is frequently used in geology and archaeology to date objects that are up to 50,000 years old.
Since carbon-14 decays steadily, it provides a trustworthy way to estimate the age of rock samples.
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A polymer has a relative molecular mass of 112000.Calculatethe number of monomers{C=12, H=1}
How many ATP does ATP produce?
The bulk of ATP production occurs during cellular respiration within the mitochondrial matrix, producing around thirty-two ATP molecules for every molecule of oxidized glucose.
What is ATP?The energy currency of the cell is ATP (adenosine triphosphate). It is a natural chemical molecule made up of phosphate groups, adenine, and the sugar ribose. These molecules supply energy to the body's many metabolic operations. Therefore, it is dubbed "Energy Currency of the Cell". ATP can be utilized to store energy for future reactions or it can be used to pay for reactions when the cell need energy. Animals use ATP to store the energy received from food breakdown. Similarly, plants use ATP molecules to collect and store the energy they receive from light during photosynthesis.
Here,
The majority of ATP is produced during cellular respiration within the mitochondrial matrix, which produces around thirty-two ATP molecules for every molecule of oxidized glucose.
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What is the height of a column of water which can be supported by a pressure of exactly 1 bar (=100 kPa = 750.0 mmHg) at 25 ℃?
Answer:
10.33 meters (33.78 feet).
Explanation:
1 bar = 10.33 mH₂O, 1 mH₂O = 0.098 bar, hence 10.33 mH₂O/0.098 bar = 10.33 m.
What physical property is characteristic of all of the elements in the group 18 of the periodic table?
The quantity of electrons inside the valence (outermost) shells as well as the electron configurations among elements belonging to the identical group are identical. They display comparable chemical characteristics.
Noble gases were low chemically reactive, odourless, colourless, nonflammable, as well as monotonic gases. Noble gases are exceedingly stable as well as uncommon to form chemical connections since they have minimal inclination to receive or lose electrons, thanks to the complete valence electron shells of such atoms.
These gases don't receive, lose, or share electrons, making them inert as well as unreactive. They are often referred to as noble gases due to their rarity inside the atmosphere of the earth.
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(Question) How many atoms are in 3 grams of Cu?
(20 points)
Answer: 2.85 x 10^22
Explanation:
We can use stoichiometry to convert grams to atoms.
*Important quantities*
Original amount of Copper: 3 grams
Molar mass of Copper: 63.5 grams
Avogadro's number: 6.022x10^23 atoms/formula units/molecules
Process - [tex]\frac{3gramCu}{1}[/tex]×[tex]\frac{1 mole Cu}{63.5 gCu}[/tex]×[tex]\frac{6.022x10x^{23} }{1 moleCu}[/tex] = 2.84503937×10^22
After taking sig figs into account, the answer needs to be rounded to 3 decimal places
Final answer: 2.85 x 10^22
calculate the solubility of AgCN in a solution containing 1.0M H Ksp of AgCN is 2.2e-12 Ka of HCN is 6.2e-10
The solubility of AgCN in a solution containing 1.0M H Ksp of AgCN is 2.2e-12 Ka of HCN is 6.2e-10 is 5.9 x 10^-2M.
Given concentration of H+ (M) = 1.0M
Ksp of AgCN = 2.2e-12
Ka of HCN = 6.2e-10
AgCN ⇋ Ag+ +CN− ................Ksp
CN − + H+ ⇋ HCN................... 1/Ka
AgCN + H+ ⇋ HCN + Ag+ ...................Ksp/Ka = K0
K0 = 2.2e-12/6.2e-10 = 0.0035 = 35 x 10-4
At Equilibrium: AgCN + H+ ⇋ HCN + Ag+
Let the moles of [Ag+] = x
So the number of moles of [HCN] = x
K0 = [Ag+] [HCN] / [H+]
35 x 10-4 = x^2/1
x = 5.9 x 10^-2M
Hence the molar solubility of AgCN in buffer solution is 5.9 x 10^-2M.
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What is an irony definition?
In literary classes, the three most popular types are verbal irony, dramatic irony, and situational irony. When a speaker or narrator says something that contradicts what they mean, what they intend, or what the context necessitates, this is called verbal irony.
What is irony?One thing is expressed while another is meant in an ironic statement. For example, on a chilly, wet gray day, you would exclaim, "What a gorgeous day!" Alternatively, if you were suffering from a severe case of food sickness, you may respond, "Wow, I feel terrific today." "ffers points of view and ideas that are, at most, intriguing... However, it does not reach the truth." Ronagh and Souder are particularly concerned with scientific assertions that are not meant to be taken seriously.
Here,
The three most common varieties in literary studies are verbal irony, dramatic irony, and situational irony. Verbal irony occurs when a speaker or narrator says something that contradicts what they mean, what they intend, or what the context requires.
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A mixture contains only NaCl and Al2(SO4)3. A 1.68-g sample of the mixture is dissolved in water and an excess of NaOH is added, producing a precipitate of Al(OH)3. The precipitate is filtered, dried, and weighed. The mass of the precipitate is 0.116 g. What is the mass percent of Al2(SO4)3 in the sample
The precipitate is collected, filtered, dried, and weighed.. The mass of the precipitate is 0.116 g.
What is dissolved?Dissolved refers to a solute that is completely dissolved in a solvent, resulting in a homogeneous mixture. When a solute, such as a salt, is dissolved in a solvent, such as water, the molecules of each component are dispersed evenly throughout the mixture. This process can be reversed by evaporating the solvent, leaving the solute behind. The amount of solute that can be dissolved in a particular solvent is known as its solubility.
Mass of Al2(SO4)3= Mass of sample- Mass of precipitate
Mass of Al2(SO4)3= 1.68-0.116=1.564 g
Percent of Al2(SO4)3= (1.564/1.68)*100= 93.45 %
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What is the energy of each of the following photons in kilojoules per mole? Express the energy in kilojoules per mole to three significant digits.
Part A: ν=5.95×1019s−1
Part B: ν=20.00×103s−1
Part C: λ=2.57×102m
The energy of a photon can be calculated using the formula: E = hν = hc/λ, where E is the energy, h is Planck's constant (6.626 x 10^-34 Js), ν is the frequency, c is the speed of light (2.998 x 10^8 m/s), and λ is the wavelength which is 6.53 x 10^-38 kJ/mol
Part A: ν = 5.95 x 10^19 s^-1
E = hν = (6.626 x 10^-34 Js) x (5.95 x 10^19 s^-1) = 3.948 x 10^-14 J/photon
To convert to kilojoules per mole, we need to divide by Avogadro's number (6.022 x 10^23 photons/mol)E = (3.948 x 10^-14 J/photon) / (6.022 x 10^23 photons/mol) = 6.53 x 10^-38 kJ/mol
Part B: ν = 20.00 x 10^3 s^-1
E = hν = (6.626 x 10^-34 Js) x (20.00 x 10^3 s^-1) = 1.325 x 10^-31 J/photon
To convert to kilojoules per mole, we need to divide by Avogadro's number (6.022 x 10^23 photons/mol). E = (1.325 x 10^-31 J/photon) / (6.022 x 10^23 photons/mol) = 2.20 x 10^-55 kJ/mol. Part C: λ = 2.57 x 10^2 m. E = hc/λ = (6.626 x 10^-34 Js) x (2.998 x 10^8 m/s) / (2.57 x 10^2 m) = 3.948 x 10^-14 J/photon. To convert to kilojoules per mole, we need to divide by Avogadro's number (6.022 x 10^23 photons/mol) .E = (3.948 x 10^-14 J/photon) / (6.022 x 10^23 photons/mol) = 6.53 x 10^-38 kJ/mol. In all the parts, the energy is expressed in kilojoules per mole to three significant digits.
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How many ATP are directly generated in the Krebs cycle when 2 molecules of glucose are oxidized?
4 ATP molecules are directly generated in the Krebs cycle when 2 molecules of glucose are oxidized
How Krebs cycle move to produce glucose molecule?The Krebs cycle, TCA cycle or the citric acid cycle, is a series of enzyme-catalyzed reactions occurring in the mitochondrial matrix and involves the oxidation of acetyl-CoA.
The acetyl group of acetyl-CoA is oxidized to make two molecules of CO2 in a succession of eight steps, while also producing one ATP. Additionally, reduced high-energy molecules like NADH and FADH2 are created.
Each glucose molecule produces two acetyl-CoA molecules, the Krebs cycle must move twice for one glucose molecule to produce the four CO2, six NADH, two FADH2, and two ATPs.
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7. Explain the role of the digestive system in animals, as well as how the system works! PLEASE I WILL GIVE BRAINLIEST
what happens to the speed of a sound wave from an underwater animal as the sound passes into the air above?
A. It stays the same
B. It falls to zero
C. It decreases
D. It increases
Oil of vitriol is a substance that humankind has known of for thousands of years! Today the substance is known by it's scientific name sulfuric acid and has the molecular formula H2SO4. What is the molar mass of H2SO4
The molar mass of H2SO4 is 98.08 g/mol. It is a combination of hydrogen with molecular weight of 1g, sulfur with 32g and oxygen with 16g and the total combination is 2x1+1x32+4x16 = 98g.
Humanity has been aware of oil of vitriol for thousands of years. The chemical name for this material is sulfuric acid, and its molecular formula is H2SO4. It is made up of sulfur, oxygen, and hydrogen molecules. Strong and hygroscopic sulfuric acid (H2SO4) has oxidizing and hygroscopic characteristics. Because it was made by roasting "green vitriol" (iron(II) sulfate) in an iron retort, sulfuric acid was known as "oil of vitriol" by medieval European alchemists. Due to its oily appearance and occurrence in vitreous or glassy substances like ferrous sulphate and alum, it is also known as the "oil of vitriol."
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Which of the following are commonly used oxidizing agents? Select all that apply. O Hydrochloric add O Sodium dichromate O Chromic acid O Sodium borohydride
Sodium dichromate and chromic acid are commonly used as oxidizing agents.
Oxidizing agents are the compounds that can either accept hydrogen or electrons from the other molecules. It is a element or compound which participates in a oxidation-reduction reaction and accept electrons from the different species. By the acceptance of electrons from other substances, oxidizing agents cause their oxidation states to become more positive. Oxidizing agents are reduced as well. They can also transfer oxygen atoms to the molecules in some of the cases. Sodium dichromate and chromic acid are used to oxidize the other inorganic salts as well as alcohols.
Hydrochloric acid is a strong acid as well as sodium borohydride is a strong reducing agent.
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A group of students is making paper airplanes. They think that the kind of paper and the design of the airplane may affect how far each paper airplane flies. The students first test if the kind of paper affects how far the airplane flies. They make several airplanes out of different kinds of paper, using the same design. Why is it important that all the airplanes have the same design? (SC. 6. N. 1. 1)
By using the same design, the students can learn about both the effect of the design and the effect of the paper.
By using the same design, the students can learn about the effect of the design.
If they do not use the same design, the students cannot learn about the effect of the paper.
It is NOT important for the airplanes to have the same design because the students are not testing the effect of the design
Students can learn about the impact of both the design and the paper by working with the same layout. Students can learn about causality in design by replicating it and seeing its effects firsthand. The pupils won't get the full benefit of the paper unless they all follow the same format. There is no need for uniformity in airplane design since pupils will not be comparing the performance of different planes.
For the first test, students conduct an experiment to evaluate whether or not different types of paper affect the airplane's range of flight. Therefore, in the first experiment, the distance the paper travels after being thrown is the dependent variable and the type of paper is the independent variable.
The airplane's design is kept constant so that any differences in flight distance can be attributed to variations in the paper used in the experiment.
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One mole of methane (CH4) and one mole of oxygen (O 2) would have the same number of atoms. Question 9 options: True False
This statement is false.
One mole of methane (CH4) contains one atom of carbon and four atoms of hydrogen, for a total of five atoms. On the other hand, one mole of oxygen (O2) contains two atoms of oxygen, for a total of two atoms. Therefore, one mole of methane and one mole of oxygen do not have the same number of atoms.
It's important to note that a mole is a unit of measurement that corresponds to the Avogadro's number of atoms, ions or molecules of a substance, which is 6.022 x 10^23 atoms, ions or molecules. That means that one mole of a substance has the same number of atoms, ions or molecules but not always the same number of elements.
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Has 13 protons and 14 neutrons what is its mass number?
An atom that has 13 protons and 14 neutrons will have mass number 27.
Rutherford demonstrated that an atom's nucleus, which is made up of protons and neutrons, contains the vast bulk of the atom's mass. The total number of protons and neutrons in an atom is referred to as the mass number. The number of protons(atomic number) and neutrons and their sum can be used to compute it.
We know that,
Mass number = Number of protons + Number of neutrons
= 13 + 14 = 27.
The mass number is 27.
Therefore an atom that have 13 protons and 14 neutrons will have mass number 27.
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What happens when ocean water that is more dense (colder or saltier) is mixed with water that is less dense (warmer or less salty)?
please make it sound like i wrote it :(
When ocean water that is more dense (colder or saltier) is mixed with water that is less dense (warmer or less salty), the denser water will sink to the bottom and the less dense water will rise to the top. This is known as stratification, and it helps to create distinct layers in the ocean.
This stratification can create an environment that is more conducive to life, as it allows different types of organisms to inhabit different layers of the ocean.
The different layers of the ocean created by stratification play a significant role in the global climate system. Colder, denser waters are usually found at the bottom of the ocean, while warmer, less dense waters are found near the surface.
This temperature difference creates a natural convection system that drives currents throughout the ocean, which helps to regulate temperatures on a global scale. Additionally, stratification can also affect the amount of oxygen in the ocean.
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The potential danger involved with ingesting certain compounds is associated with their solubility in the body's aqueous environment. Which of the following would be most soluble in water ?
A.CH3CH2OH
B. CH3CH2CH2OH
C. CH3OCH2CH3
The solubility of a compound in water is determined by the type of chemical bonds present in the compound and the polarity of the molecule. Thus option B is the correct answer.
Compounds that are polar and have hydrogen bonding capability are more likely to be soluble in water.
In this case, Propanol (CH3CH2CH2OH) has a polar -OH group, which makes it able to form hydrogen bonds with water molecules, and therefore it would be more soluble in water than the other two compounds.
The other two compounds, CH3CH2OH (Ethanol) and CH3OCH2CH3 (Dimethyl ether), also have polar groups, but propanol has the most polar -OH group which is why it would be the most soluble in water.
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Solid silicon and solid magnesium chloride form when silicon tetrachloride gas reacts with magnesium metal. Write a word equation and an unbalanced formula equation including physical states.
Solid silicon and solid magnesium chloride form when silicon tetrachloride gas reacts with magnesium metal. the equation is :
SiCl₄(g) + Mg(s) ---> Si(s) + MgCl₂(s)
When the solid silicon react with the solid magnesium chloride , the word equation is :SiCl₄(g) + Mg(s)
the product formed is the silicon tetrachloride gas. the word equation is :
Si(s) + MgCl₂(s)
The unbalanced equation is :
SiCl₄(g) + Mg(s) ---> Si(s) + MgCl₂(s)
The balanced equation for the reaction of the silicon tetra chloride react with the magnesium and form the silicon and the solid magnesium chloride. and t is given :
SiCl₄(g) + Mg(s) ---> Si(s) + MgCl₂(s)
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For parts of the free response question that require calculations, clearly show the method used and the steps involved in arriving at your answers. You must show your work to receive credit for your answer. Examples and equations may be included in your answers where appropriate. Answer the following questions related to the analysis of CaBr2. (a) A student has a 10.0g sample of CaBr2. Show the setup of the calculation to determine the number of moles of CaBr2 in the sample. Include units in the setup. (You do not need to do any calculations.)
10.0g of CaBr2 contains 0.05 mol according to the equation mole(n) = mass / molar mass (10.0g CaBr2 x 1 mol CaBr2 / 199.88 g CaBr2 = 0.05 mol)
What exactly does the word "mole" mean?The mole, represented by the symbol mol, is the SI unit of material quantity. One mole is made up of precisely 6.022*1023 elementary components. The Avogadro number, NA, as expressed in mol1, is the fixed numerical expression of the Avogadro number.
Is a mole considered a mass unit?The weight in grams of 1 mole of a certain substance is its molar mass. The atomic mass of the chemical unit, expressed in atomic mass units, determines the mass of a substance (amu).
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Convert the following numbers into the standard form of scientific notation 0. 010x 10e5
The standard form of scientific notation for 0. 010x 10e5 is 1.0 × 10^3.
Scientific notation is a form of presenting large numbers or very small numbers in a simpler form.
There are some rules to write scientific notation:
The base should be always 10. The exponent must be a non-zero integer.
Absolute value of the coefficient should be greater than or equal to 1 but it should be less than 10.The mantissa carries the rest of the significant digits of the number.
The power of 10 will be positive, if the given number is multiples of 10 then the decimal point has to move to the left. The power of 10 will be negative If the given number is smaller than 1 and then the decimal point has to move to the right.
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When your hand blocks your view of the lamp, where does the shadow of your hand fall?
Please help this is due today and I really need help
Answer:
on your face
Explanation:
because when the light is falling on your hand (which already blocked your view of the lamp) then the shadow will fall on your face
Exercise 3.1 Evaporation
In this exercise, you will think about what evaporation is and how it happens.
1 Complete these sentences. Choose the correct word when there
is a choice.
Evaporation occurs when a
turn into a
The particles in the liquid
turns into a
gain/lose
and move faster/slower and closer
together/further apart until some of them escape from the surface and
become a
Evaporation occurs when a liquid turns into vapour . The particles in the liquid gain energy and move faster and further until some of them escape from the surface and become a vapour
What is Evaporation ?A type of vaporisation called evaporation takes place on the surface of a liquid as it transitions into the gas phase. When humidity impacts the rate of evaporation of water, for example, a high concentration of the evaporating substance in the surrounding gas considerably slows down evaporation.A liquid transforms into a gas during evaporation. It is simple to picture when puddles of rain "vanish" on a hot day or when wet clothing dries in the sun. In these instances, the liquid water is evaporating into a gas known as water vapour rather than really dissipating. Global evaporation takes place.Evaporation occurs on surfaces. The top layer of the liquid evaporates because the molecules with the highest kinetic energy escape into the air, causing it to become lighter.
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Suppose of sodium bromide is dissolved in of a aqueous solution of silver nitrate. Calculate the final molarity of bromide anion in the solution. You can assume the volume of the solution doesn't change when the sodium bromide is dissolved in it.
The final molarity of bromide anion in the solution when of sodium bromide is dissolved in of a aqueous solution of silver nitrate is 0.59M
Given the mass of sodium bromide (m) = 15.3g
Volume of aqueous solution of silver nitrate (V) = 250ml = 0.25L
Concentration of solution of silver nitrate (M1) = 0.40M
Let the final molarity of sodium bromide = M2
The volume of solution does not change when when sodium bromide is dissolved in it.
The aqueous solution of silver nitrate contains AgNO₃ ⇆ Ag⁺ +NO₃
Sodium bromide is dissociated as: NaBr ⇄ Na⁺ + Br ⁻
If we know the molecular weight of NaBr, we can directly calculate the ultimate molarity of the bromide ion (Br) from the molarity of NaBr by using the formula:
NaBr has a molecular weight of 102.89 g/mol.
So, M2 = (m/V) x 1mol of NaBr/Molec weight
= (15.3/0.25 )x 1 mol of NaBr/102.89 = 0.59mol/L = 0.59M
Hence the final molarity of bromide anion in the solution is 0.59M.
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complete question: Suppose 15.3g of sodium bromide is dissolved in 250.mL of a 0.40 M aqueous solution of silver nitrate. Calculate the final molarity of bromide anion in the solution. You can assume the volume of the solution doesn't change when the sodium bromide is dissolved in it.
Why do the electrons stay in between the nuclei of the two hydrogen atoms chemthink
Electrons stay in between the nuclei of the two hydrogen atoms because they are attracted to the positive charge of the nuclei.
Electrons are negatively charged species, so they are attracted towards the positive charge of a nucleus.
In hydrogen atom, when both the two hydrogen atoms get close to each other then the electrons of each atom will get attracted to both the nuclei. And if both the hydrogen atoms come close to each other they will repel each other.
The energy of the two hydrogen atoms becomes less when they are together than when they are far apart.
Thus, the electrons tend to stay in between the nuclei of the two hydrogen atoms.
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