The empirical formula for the compound is therefore C₂H₄O, which means that it contains two carbon atoms, four hydrogen atoms, and six oxygen atoms.
The empirical formula for an organic compound is the simplest whole-number ratio of the numbers of atoms of each element in the compound.
To find the empirical formula for an unknown compound with a percent composition of 26.09% carbon, 4.35% hydrogen, and 69.56% oxygen, we can use the following equation:
Empirical formula = (atomic mass of carbon) / (number of carbon atoms) × (1/12) + (atomic mass of hydrogen) / (number of hydrogen atoms) × (1/2) + (atomic mass of oxygen) / (number of oxygen atoms)
First, we can use the atomic mass of carbon, which is 12.01 g/mol, to find the number of carbon atoms in the compound:
number of carbon atoms = (atomic mass of carbon) / (atomic mass of carbon/mol)
number of carbon atoms = 12.01 g/mol / 12 g/mol
number of carbon atoms = 1 g/mol
Next, we can use the number of carbon atoms and the percent composition of carbon to find the molar mass of the compound:
Molar mass = (number of atoms of an element) × (atomic mass of an element/mol)
Molar mass = (number of carbon atoms) × (12 g/mol)
Molar mass = 1 g/mol
We can use the molar mass and the percent composition of each element to find the number of moles of each element in the compound:
Number of moles of carbon = (molar mass of carbon) / (molar mass of carbon/mol)
Number of moles of carbon = 1 g/mol / 12 g/mol
Number of moles of carbon = 0.00833 mol
Number of moles of hydrogen = (molar mass of hydrogen) / (molar mass of hydrogen/mol)
Number of moles of hydrogen = 1 g/mol / 1 g/mol
Number of moles of hydrogen = 1 mol
Number of moles of oxygen = (molar mass of oxygen) / (molar mass of oxygen/mol)
Number of moles of oxygen = 16 g/mol / 16 g/mol
Number of moles of oxygen = 1 mol
We can use the number of moles of each element and the empirical formula to find the number of atoms of each element in the compound:
Number of atoms of carbon = number of moles of carbon / Avogadro's number
Number of atoms of carbon = 0.00833 mol / 6.022 x 10²³ atoms/mol
Number of atoms of carbon = 1.35 x 10²²atoms of carbon
Number of atoms of hydrogen = number of moles of hydrogen / Avogadro's number
Number of atoms of hydrogen = 1 mol / 6.022 x 10²³ atoms/mol
Number of atoms of hydrogen = 1.67 x 10²² atoms of hydrogen
Number of atoms of oxygen = number of moles of oxygen / Avogadro's number
Number of atoms of oxygen = 1 mol / 6.022 x 10²³ atoms/mol
Number of atoms of oxygen = 1.67 x 10²² atoms of oxygen
The empirical formula for the compound is therefore C₂H₄O, which means that it contains two carbon atoms, four hydrogen atoms, and six oxygen atoms.
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At a particular temperature, the solubility of Kr in water is 0.060 M when the partial pressure is 0.90 atm. What partial pressure (in atm) of Kr would give a solubility of 0.150 M
At a particular temperature, the solubility of He in water is 0.060 M when the partial pressure is 0.90 atm. 2.27 atm is the partial pressure of Kr would give a solubility of 0.150 M.
What is Henry's Law ?According to Henry's law, the weight of a gas dissolved by a liquid is proportional to the pressure of the gas onto the liquid.With very few exceptions, a solute molecule in an extremely diluted solution will only have solvent molecules as its close neighbors. This means that the likelihood that a specific solute molecule will escape into the gas phase is predicted to be independent of the total concentration of solute molecules.Solution:
The solubility of gas is directly proportional to partial pressure. It is expressed as:
S = [tex]K_ h \times P _g_a_s[/tex]
where, S = Solubility of gas
[tex]K_h[/tex] = Henry's Law constant
[tex]P_g_a_s[/tex] = Partial pressure of gas
Now, put the values in above expression we get
0.060M = [tex]K_h[/tex] × 0.9 atm
[tex]K_h[/tex] = = 0.066 M/atm
Now we have to find the partial pressure of He
0.150 M = 0.066 M/atm × [tex]P_g_a_s[/tex]
[tex]P_g_a_s[/tex] = 2.27 atm
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Is copper and silver nitrate a physical change or Chemical change
Explanation:
One of the most fascinating chemical experiments is the reaction between silver nitrate and copper wire in water. Characterised by fractal-like precipitates, this experiment is a stunning example of a simple redox reaction.
Copper reacting with silver nitrate is a chemical change. In a chemical change, new substances are formed with different chemical properties.
Copper (Cu) is a metal, and silver nitrate is a compound made of silver (Ag), nitrogen (N), and oxygen (O).When copper is added to silver nitrate, a reaction occurs. The copper atoms react with the silver nitrate molecules, resulting in the formation of new substances.
The reaction produces copper nitrate and silver (Ag) as products.Copper nitrate is a compound formed by the combination of copper, nitrogen, and oxygen, while silver remains unchanged.
The color of the solution changes, indicating a chemical reaction has taken place. Copper nitrate is usually a blue-green color, while silver is a metallic silver color.The chemical properties of the substances involved in the reaction are altered. Copper, being a metal, is malleable and conducts electricity, whereas copper nitrate is a compound and does not possess these properties.
Thus, the reaction between copper and silver nitrate is a chemical change because new substances with different properties are formed.
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Engine cooling fluid is a. distilled water. b. tap water from a faucet. c. a mixture of alcohol and water. d. a mixture of antifreeze and water.
Engine cooling fluid is a mixture of antifreeze and water.
Hence option (d) is correct.
A liquid mixture of water and antifreeze called engine coolant is kept in your car's radiator.
Any compound that lowers water's freezing point is considered antifreeze and protects a system against the negative effects of ice formation.
Radiators are protected from deterioration by antifreezes, which are frequently added to water in car cooling systems.
It keeps your engine from freezing in extremely cold weather or overheating in hot weather, both of which can cause serious problems for an engine.
Although it's standard practice to combine water and antifreeze 50/50 in a car's cooling system, this guideline is not inflexible.
Mixtures can be changed to either raise the boiling point or lower the freezing point limit due to the wide range of weather conditions that cars can operate in.
Hence, Engine cooling fluid is a mixture of antifreeze and water.
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The volume occupied by 0.4g of hydrogen gas at S.T.P is ________
{H=1.00, Molar volume at S.T.P =22.4dm^3
Answer:
4.48 dm^3
Explanation:
As given in the problem, the conversion factor for the molar volume of all gases is 22.4 dm^3/mole at STP. A mole of all ideal gases will occupy 22.4 liters (dm^3). Calculate the moles of hydrogen contained in 0.4 grams of the gas by dividing the mass by the molar mass of H2. H2 has a molar mass of 2 grams/mole.
(0.4 g)/(2 grams/mole) = 0.2 moles H2
(0.2 moles H2 at STP)*(22.4 dm^3/mole at STP) = 4.48 dm^3 (4.48 liters at STP)
Calculate the number of atoms in 3 mol helium
Answer:
1.81 x 10²⁴ atoms He
Explanation:
You can find the amount of atoms by multiplying the given moles by Avogadro's Number. This number represents the amount of atoms per 1 mole. It is important to arrange the ratio in a way that allows for the cancellation of units.
Avogadro's Number:
6.022 x 10²³ atoms = 1 mole
3 moles He 6.022 x 10²³ atoms
-------------------- x -------------------------------- = 1.81 x 10²⁴ atoms He
1 mole
A radioisotope decays, producing an alpha particle and th-234. the original radioisotope must have been an atom of?
If the product of the process is Th-234, the we now know that the original atom must be U-238.
What is an alpha decay?An alpha decay is said to occur when there is the loss of an alpha particle from an atom. Now we know that when there is a loss of an alpha particle, the mass number is decreased by 4 four units while the atomic number is decreased by two units.
If the product of the process is Th-234, the we now know that the original atom must be U-238. It is found two places after the thorium atom in the periodic table.
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The statement, in a mixture of gases, the total pressure is the sum of the individual partial pressures of gases in the mixture paraphrases ________.
Dalton's law
States that the total pressure exerted by a mixture of gases is the sum of the pressures exerted independently by each gas in the mixture.
What is Dalton's law of partial pressure ?Dalton's law, which states that a gas mixture's overall pressure is equal to the sum of its component gases' partial pressures. The pressure that each gas would produce if it occupied the same volume of the mixture by itself at the same temperature is known as the partial pressure.
The pressure that each gas would produce if it occupied the same volume of the mixture at the same temperature alone is referred to as the partial pressure.Learn more about Dalton's law of partial pressure here:
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This table resembles a condensed version of the modern periodic table. Using the full periodic table as a reference, type the symbols for the elements from part A into this table based on their appropriate group and period.
re write the question.
Explanation:
it seems incomplete.
What is the name of the molecule below?
G
O A. Ethyne
O B. Ethene
C. Methene
OD. Methyne
H-C=C-H
The name of the molecule above is Ethene
What are organic compounds?Organic compounds can be defined as compounds containing carbon and hydrogen.
Some classes of organic compounds are:
AlkanesAlkenesAlkanolsAlkanalsAlkynesSo therefore, he name of the molecule above is Ethene
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What is the coefficient for oh−(aq) when s2−(aq) no3−(aq) → s(s) no(g) is balanced in basic aqueous solution?
From the balanced redox equation of the reaction, the coefficient of OH⁻ is 8.
What is the balanced redox equation of the reaction?A redox equation is the equation of a redox reaction in which oxidation and reduction occurs simultaneously.
The given redox reaction takes place in a basic solution
The balanced redox equation of the reaction is given below:
4 H₂O(l) + 3 S²⁻(aq) + 2 NO₃⁻(aq) ---> 3 S(s) + 2 NO + 8 OH⁻(aq)
In conclusion, a redox equation is balanced when oxidation and reduction occur to the same extent.
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What is occurring when reactants are mixed and heated and liquid collects in the sidearm of the apparatus
When reactants are mixed and heated and liquid collects in the sidearm of the apparatus, a chemical reaction is occurring.
What is a chemical reaction?A chemical reaction is said to occur when reactants are combined to form products. We must note that the formation of products is evidenced by;
Appearance of a liquidAppearance of a gas Appearance of a solidHence, when reactants are mixed and heated and liquid collects in the sidearm of the apparatus, a chemical reaction is occurring.
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What do you think the elements that are in the same group or period on the periodic table have in common?
chemical properties and same number of shell
Explanation:
elements in the same group have the same number of eletrons in their outermost shell and hence have the same chemical properties
State whether it would be worthwhile to investigate finding a catalyst to use in this reaction under standard conditions and explain why?.
Yes, it will be worthwhile to investigate finding a catalyst to use in this reaction under standard conditions because it is negative.
What is a Catalyst?This is a substance which speeds up the rate of a chemical reaction by lowering the activation energy.
ΔG being negative indicates a a slow reaction which is why a catalyst under standard conditions should be used.
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Amines suitable for preparing buffers are often synthesized by treating ammonia with epoxides. Consider the following series of reactions, and draw the structure of compound B.
It is correct to state that Amines are suitable for preparing buffers are often synthesized by treating ammonia with epoxides. The relative structures of compound B are attached accordingly.
What is an Amine?Amine is a family of basic chemical compounds formed by replacing hydrogen with one or more monovalent hydrocarbon radicals.
Apart from medications and pharmaceuticals, amines are employed in the production of azo-dyes and nylon.
They are commonly employed in the development of crop protection, pharmaceutical, and water purification chemicals. They are also used in personal care products.
Ethanol amines are the most widely utilized form of amine on the global market.
It should be noted that ammonia attacks epoxides at the least substituted carbon to produce (A.)
The generated product is then made to react with another epoxide, resulting in the synthesis of successive products.
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A physical change involves a change in the identity o the sample.
O True
O False
Use the following, balanced equation for the question below:
2Al(s) + 3CuCl₂(aq) → 3Cu(s) + 2AlCl3(aq)
How many moles of aluminum are needed to produce 50.0 grams of aluminum chloride?
Answer:
0.375 moles Al
Explanation:
To find the moles Al, you need to (1) convert grams AlCl₃ to moles AlCl₃ (via molar mass) and then (2) convert moles AlCl₃ to moles Al (via mole-to-mole ratio from equation coefficients). It is important to arrange the ratios/conversions in a way that allows for the cancellation of units. The final answer should have 3 sig figs to match the sig figs of the given value (50.0 g).
Molar Mass (AlCl₃): 26.982 g/mol + 3(35.453 g/mol)
Molar Mass (AlCl₃): 133.341 g/mol
2 Al(s) + 3 CuCl₂(aq) -----> 3 Cu(s) + 2 AlCl₃(aq)
50.0 g AlCl₃ 1 mole 2 moles Al
-------------------- x ------------------ x ----------------------- = 0.375 moles Al
133.341 g 2 moles AlCl₃
is glycine mono functional?
Answer:
Yes
Explanation:
Answer:it act as a precursor to proteins
Explanation:
Which fundamental mechanisms appear in the reaction between pyridinium chlorochromate and a secondary alcohol
The idea is to foretell the formation of a carbonyl compound by the reaction between alcohol and too much pyridinium chlorochromate. An oxidizing agent called pyridinium chlorochromate converts the alcohol group into the 1carbonyl group.
The carbonyl molecule that results from the reaction will depend on the reactant's OH group. Pyridinium chlorochromate [PCC] converts primary OH to aldehydes, whereas it converts secondary OH to ketones, and oxidation of tertiary OH has little effect. Alcohols and pyridinium chlorochromate [PCC] react to create a carbonyl molecule.
From primary alcohols to aldehydes and from secondary alcohols to ketones, pyridinium chlorochromate oxidizes alcohols one step up the oxidation ladder. pyridinium chlorochromate will not oxidize aldehydes to carboxylic acids, in contrast to chromic acid. Comparable to Pyridine (the Collins reagent) and CrO3 will both oxidize primary alcohols to aldehydes. Here are two instances of pyridinium chlorochromate being used.
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when in extinguishing agent is determined to be safe and effective for you from combustible Metals it will
Dry powder extinguishers
They are for Class D or combustible metal fires, only. They are ineffective on all other classes of fires.
What is an Extinguishing agent ?Extinguishing Agent means a source of extinguishment in which to quickly and effectively suppress the fire.
They consist of ABC Dry Chemical, BC Dry Chemical, Dry Powder, Water, Foam, Wet Chemical, Halogenated, and Carbon Dioxide. Dry Chemical extinguishers: Dry chemical extinguishers are the most common and available in few types.Learn more about Extinguishing agent here:
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Radiometric dating allows scientists to figure out the absolute age of an event.
A. What is a half-life?
B. Which of these four radioactive elements would you choose to date a specimen from the most recent epoch?
Half-life in geology is defined as the time it takes for a radioactive material or element to decay half its original quantity into a daughter radiogenic isotope.
From the radioactive elements listed the Carbon-14 would be most preferable for dating a specimen.
What is radiometric dating?Radiometric dating is defined as the process that is used by scientists to calculate the age of geologic materials.
From the data given in the table above, the radioactive element with the most recent half-life is carbon-14 being 5,730 years.
The uses os Carbon-14 include the following:
Used to measure the age of wood,Used to measure sources of chloride and the age of waterResearchers can use that decay as a kind of clock that allows them to peer into the past.Used in studying abnormalities of metabolism that underlie diabetes, gout, anemia, and acromegaly.The carbon-14 is preferably used for dating specimen because it is the most stable and accurately dates archaeological artifacts.
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The solubility of lead(II) chloride is 0.45 g/100 mL of solution. What is the Ksp of PbCl2?a. 8.5 ? 10^-6b. 4.2 ? 10^-6c. 1.7 ? 10^-5d. 4.9 ? 10^-2e. < 1.0 ? 10^-6
The solubility of lead(II) chloride is 0.45 g/100 mL of solution. The value of [tex]K_{sp}[/tex] of [tex]PbCl_{2}[/tex] is 1.7×[tex]10^{-5}[/tex] .
So, option C is correct one.
Calculation,
Number of moles of [tex]PbCl_{2}[/tex] = mass/molar mass = 0.45/278.1 = 1.618×[tex]10^{-3}[/tex] moles
Concentration of [tex]Pb^{+2}[/tex] and [tex]Cl^{-}[/tex] ion
Molarity of [tex]Pb^{+2}[/tex] = Number of moles of solute /volume in lit
Molarity of [tex]Pb^{+2}[/tex] = 1.618×[tex]10^{-3}[/tex] moles /0.1 lit = 0.0162 M
[tex]PbCl_{2}[/tex] → [tex]Pb^{+2}[/tex] + 2[tex]Cl^{-}[/tex]
For certain amount of [tex]Pb^{+2}[/tex] , twice this amount of [tex]Cl^{-}[/tex] ion formed.
The concentration of [tex]Cl^{-}[/tex] ion formed = 2× 0.0162 M = 0.0324 M
Now,
The solubility of lead(II) chloride of solution = 0.45 g/100 mL
[tex]K_{sp}[/tex] of [tex]PbCl_{2}[/tex] = [ [tex]Pb^{+2}[/tex] ][tex][Cl^{-}]^{2}[/tex] = 0.0162 ×[tex][0.0324 ]^{2}[/tex] = 1.7×[tex]10^{-5}[/tex] .
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The half-life of cesium-137 is 30 years. Suppose we have a 150 mg sample. (a) Find the mass (in mg) that remains after t years.
The half-life of cesium-137 is 30 years. Suppose we have a 150 mg sample. The masses (in mg) that remains after t years A=150/2^t/30yrs
what do you mean by half-life?A substance's half-life is the amount of time it takes for half of it to decompose.
What is a half-life example?Half-life is the length of time it takes for half of an unstable nucleus to go through its decay process. A radioactive element's half-life decay time varies depending on the element. For instance, carbon-10 has a half-life of only 19 seconds, making it impossible to discover in nature. On the other hand, uranium-233 has a half-life of almost 160000 years.
When n half-lives have passed, the formula for estimating the amount still left is:-
A=A°/2^n
where,
A=initial amount
A°=remaining amount
n=t/t_{1/2}
A=150/2^t/30yrs
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Place the items in order from lowest to highest degree of internal organization
The order of internal organization from lowest to highest degree is; cell < tissue < organ < organ system
What is the order of organization?The complexity of the parts that compose an organism lays the bedrock for the classification of life. Some organisms are composed only of one cell while others are composed of many complex systems.
The order of internal organization from lowest to highest degree is; cell < tissue < organ < organ system
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Missing parts:
Place the items in order from lowest to highest degree of internal organization.
1.organ system
2.tissue
3.cell
4.organ
What is the concentration, in ppb, of
PCB's in a chemical spill, if there
are 6.0 x 10-5 g in 4,600 kg of soil?
Answer:
1ppm = 1 mg/kg
60460 = 0.13
0.13
Explanation:
Answer:0.013 ppb
Explanation:
When a hydrogen atom is part of a molecular structure, it is always a ___________ atom.
Answer:
terminal
Explanation:
When a hydrogen atom is part of a molecular structure, it is always a terminal atom.
Substances composed of atoms that all have the same number of protons are called:.
The substances composed of atoms that all have the same number of protons are called elements.
What are the names of substances made up of atoms with the same number of protons?
The substances which are made up of atoms with the same numbers of protons are called as element.
An element is a substance with the same number of protons in all of its atoms. Gold is an example of an element. A pure gold bar is made up of only one element, gold.
All matter is composed of substances known as elements, which have distinct chemical and physical properties and cannot be broken down into other substances via ordinary chemical reactions.
Gold, for example, is an element, as is carbon. Only 92 of the 118 elements occur naturally. The remaining elements are unstable because they were only created in laboratories.
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In the reaction catalyzed by the pyruvate dehydrogenase complex, the two carbons constituting the acetyl group are.
In the reaction catalyzed by the pyruvate dehydrogenase complex, the two carbons constituting the acetyl group are oxidized by NAD+ while attached to the lipoamide.
Pyruvate dehydrogenase influencing the reaction:A multienzyme complex called pyruvate dehydrogenase (PDH) catalyzes the oxidative conversion of pyruvate into acetyl coenzyme A (CoA), carbon dioxide (CO2), and reducing equivalents in the form of NADH.
Reaction:The pyruvate dehydrogenase complex catalyzes the oxidative decarboxylation of pyruvate to the acetyl group of acetyl-CoA.This complex requires the sequential action of three different enzymes and five different enzymes and five different coenzymes or prosthetic groups - Thiamine pyrophosphate(TPP), flavin adenine dinucleotide(FAD), coenzyme A(CoA-SH), Nicotinamide adenine dinucleotide(NAD).To learn more about catalysis visit:
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As a reaction proceeds toward equilibrium from reactants to products (i.e., from left to right as written), the value of Q is
As a reaction proceeds toward equilibrium from reactants to products, the value of Q is Increasing
Equilibrium can exist in chemical processes (the products and reactants are produced at the same rate). In a reversible chemical reaction, chemical equilibrium is the state in which there is no net change in the quantity of reactants or products. When a chemical reaction is reversible, the products react with the original reactants as soon as they are created.
There is no net change in the quantity of the chemicals involved when the two opposing reactions are in equilibrium because they are occurring at identical rates, or velocities. At this point, the reaction may be deemed to be finished, meaning that the maximum amount of reactants to products has been converted under the given reaction conditions.
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Potassium carbonate dissolves as follows:
K2CO3(s) → 2k (aq) CO3^2-(aq).
What volume in liters of 1.0 m k2co3 solution is required to provide 0.50 moles of k (aq)?
The 0.25 volume in liters of 1.0 M [tex]K_{2}CO_{3}[/tex] solution is required to provide 0.5 moles of [tex]K[/tex](aq).
Calculation,
The Potassium carbonate dissolves as follows:
[tex]K_{2}CO_{3}(s)[/tex] → [tex]2K(aq) +[/tex][tex]CO_{3}^{-2} (aq)[/tex]
The mole ratio is 1: 2
It means, the 1 mole [tex]K_{2}CO_{3}[/tex] required to form 2 mole of [tex]K[/tex](aq).
To provide 0.5 mole of [tex]K[/tex](aq) = 1 mole ×0.5 mole /2 mole required by [tex]K_{2}CO_{3}[/tex].
To provide 0.5 mole of [tex]K[/tex](aq) ,0.25 mole required by [tex]K_{2}CO_{3}[/tex].
The morality of [tex]K_{2}CO_{3}[/tex] = 1 M = number of moles / volume in lit
The morality of [tex]K_{2}CO_{3}[/tex] = 1 M = 0.25 mole/ volume in lit
Volume in lit = 0.25 mole / 1 M = 0.25 mole/mole/lit = 0.25 lit
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The oxidation number is often referred to as the _____. redox factor oxidation state spectator ion reducing factor
The oxidation number is often referred to as the oxidation state.
The number of electron/electrons which completely transferred and induced charged on an atom is called oxidation state of an atom. It is also describe as the number that is allocated to elements in a chemical combination. The number of electron that atoms in a molecule can share while forming chemical bonds with other atoms of a different elements. The oxidation number of the monoatomic (composed by atom) ion is the same as the charge of the ion.
The primary distinction between oxidation number versus oxidation state would be that the former refers to the charge that would be placed on the central atom of a coordination complex if every one of the connections around it were ionic bonds, while the latter relates to the number of electrons that an atom could either receive, lose, or share with some other atom.
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