The bubbles that you feel on your tongue when you drink soda pop are due to what chemical substance?

The pH(power of hydrogen) will be 7.18.

A buffer solution is an aqueous combination of a weak acid and either its conjugate base or base itself. When a modest amount of a strong acid or base is applied to it, the pH hardly changes at all.

Acidic Buffer: This substance is created when a strong base is combined with a weak acid and its salt.

Basic Buffer: This substance is created when a strong acid and a weak base with its salt are combined.

pH = pKa + log {[salt]- 0.002 moles HCl / [Acid]+ 0.002moles HCl

      = 7.2 + log {0.1 -0.002/ 0.1+0.002}

pH = 7.18

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The concept that each one matter is made up of tiny units called atoms was first proposed by Leucippus and Democritus, within the fifth century B.C. Dalton , in 1808 postulated that matter is formed of atoms, which are small indivisible particles

The atomic theory of matter was first proposed by Dalton in 1808. Dalton atomic theory regarded the atom because the ultimate particle of matter.

In 1898, J.J Thomson, proposed that an atom possess a spherical shape during which positive charge is distributed uniformly and the electrons are embedded into it. So his model is named plum pudding model

Rutherford established his model in 1900. He found that, most space of an atom is empty and charged particle concentrated at the center of an atom called nucleus.

In 1913, Neils Bohr improved the model proposed by Rutherford. consistent with his concept electrons orbit the nucleus.

Erwin Schrödinger, in 1926 proposed electron cloud model. He explains the probability of finding electrons.

Hence, we will conclude that the order the sequence of ideas that led to the current model of the atom is,

1. Dalton developed the idea that all matter is made of atoms.

2. Thomson discovered that atoms contain electrons.

3. Rutherford discovered that atoms have a nucleus.

4. Bohr developed the model during which electrons orbit the nucleus.

5. Schrödinger developed the electron cloud model of the atom.

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Activity would be expected for a 25.3 mg sample of carbon-14 is 25.296

Here given data is Carbon-14 has a half-life of 5730 yrs and expected for a 25.3 mg sample of carbon-14 =?

So here half life of Carbon-14 is t1/2=5730 yrs

This means that 5730 yrs the initial amount of carbon-14 will be halved

The radioactive constant is λ=ln2/t1/2 = ln2/5730=0.000121

The fundamental decay equation is m=m0e⁻λt

Initial amount of carbon-14 is m0=25.3

Therefore, 25.3×e⁰⁰⁰⁰¹²¹=25.296

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Answer:

A table is displaying data or information in rows and columns. A chart, on the other hand, is a graphical display of information wherein the information is illustrated in symbols such as bars, lines, or slices.

Explanation:

Answer:

synthesis and decomposition has a high scientific value as synthesis and decomposition are one of the most important types of chemical reactions to occur in the nature. A chemical reaction is defined as the formation or breaking of chemical bonds between atoms to form new combinations of atoms. The atoms or combination of atoms involved in a chemical reaction is referred to as reactants and the newly formed substances are known as products. All the chemical reactions occur in the biological system are categorized into four types; synthesis reactions, decomposition reactions, exchange reactions, and reversible reactions. In this article, the difference between synthesis and decomposition will be discussed broadly.

Explanation:

What are the differences between Synthesis and Decomposition?•

Decomposition is the opposite of synthesis.•

Synthesis is the process of the formation of new bonds between reactants to form new products, whereas decomposition is the breaking of chemical bonds within reactants to form different products.•

Synthesis requires energy, whereas decomposition release energy.•

Decomposition reactions are collectively called catabolism, whereas synthesis reactions are called anabolism.•

Synthesis involved in the growth of body parts and repair body tissues. Decomposition takes place during the digestion of foods.

The flavoring agent in club soda is the chemical potassium bicarbonate. This is an illustration of an emergent property because it is composed of potassium, carbon, hydrogen, and oxygen.

What is an emergent property?

An entity acquires an emergent attribute as it integrates into a larger system. Living things benefit from emergent qualities that enable them to survive by better adjusting to their surroundings.

By joining together to form the proteins, lipids, carbohydrates, and nucleic acids that comprise macromolecules, atoms like carbon, hydrogen, oxygen, and nitrogen found in molecules acquire new or emergent capabilities. Lipids are created, for instance, when particular combinations of carbon, hydrogen, and oxygen occur. Lipids have the ability to create cell membranes, which keep living cells isolated from their surroundings. Life could not exist without cell membranes, which are an emergent feature not present in the molecules that comprise them.

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The Ph of a 0.15 m aqueous solution of Na Br O (the sodium salt of H Br O) is 10.7. what is the k a for H Br O is 6.0[tex]E^{-9}[/tex].

An aqueous solution is a solution in which solvent is water. It is mostly shown in chemical equations by appending (a q) to relevant chemical formula. For example, solution of table salt, or sodium chloride (NaCl), in water would be represented as Na+(a q) + Cl−(a q). The word aqueous (which comes from aqua) means pertaining to, related to, similar to, or dissolved in, the water. As water is an excellent solvent and is also naturally abundant, it is ubiquitous solvent in chemistry. Since water is frequently used as solvent in experiments, the word solution refers to an aqueous solution, unless the solvent is specified.

A non-aqueous solution is a solution in which solvent is a liquid, but is not water.

Reactions in aqueous solutions are usually the metathesis reactions. Metathesis reactions are another term for the double-displacement; that is, when a cation displaces to form an ionic bond with the other anion. The cation bonded with latter anion will dissociate and bond with the other anion.

A common metathesis reaction in the aqueous solutions is a precipitation reaction. This reaction occurs when two aqueous strong electrolyte solutions mix and produce insoluble solid, also known as a precipitate. The ability of a substance to dissolve in water is determined by whether substance can match or exceed the strong attractive forces that water molecules generate between themselves. If the substance lacks the ability to dissolve in water, molecules form a precipitate.

When writing the equations of precipitation reactions, it is essential to determine precipitate. To determine the precipitate, one must consult chart of solubility. Soluble compounds are aqueous, while the insoluble compounds are the precipitate. There may not always be precipitate. Complete ionic equations and net ionic equations are used to show the dissociated ions in metathesis reactions. When performing the calculations regarding the reacting of one or more aqueous solutions, in general one must know the concentration, or molarity, of the aqueous solutions.

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Water solubility affect signaling molecules because water soluble ligand are polar and therefore cannot pass through plasma membrane

Hydrophobic molecule can diffuse through the plasma membrane and bind to internal receptor water soluble ligand are unable to pass free through the plasma membrane due to their polarity and must bind to an extracellular of the cell. there are so many signals are insoluble in water. signaling molecules are classified in two type hydrophilic and hydrophobic in which hydrophilic signaling molecules are binding to receptors proteins while hydrophobic signaling molecules are transport through bloodstream attached to hydrophilic center.

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Compounds can be created by chemically combining elements, hence a compound is made up of two or more elements combined in specific ratios. Ionic or covalent bonds between the atoms of constituent elements can be used to create compounds.

What are substances, exactly?

A matter with certain qualities and makeup is referred to as a substance. Every pure element and compound counts as a substance. Pure substance made of hydrogen and oxygen is called water, or H2O. Each homogenous pure substance exists.

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The density of an unknown metal object if its mass is 53.72 g and it displaces 7.9 ml of water is 6.8 g/mL.  

Density may be defined as a type of physical property that significantly deals with the description of how much space an object or substance takes up with respect to the amount of matter in that object or substance.

In a more simple sense, it is characterized as the measurement of quantity or mass per unit of volume in a particular substance.

According to the question,

The mass of the metal object = 53.72 g.

The volume of the metal object = 7.9 ml.

The formula for calculating the density is as follows:

                      = 53.72 g / 7.9 ml = 6.8 g/mL.

Therefore, the density of an unknown metal object if its mass is 53.72 g and it displaces 7.9 ml of water is 6.8 g/mL.  

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The material with a mass of 45 grams occupies a space of 1 cubic centimeter, the measurement given is density.

What is density?

Any unit that is defined as mass divided by volume is a mass density according to the density equation ( = m/V). There are numerous units for mass density in use due to the great number of units of mass and volume used to represent a wide range of magnitudes.

The two units for density that are perhaps most frequently used are the SI unit of kilogram per cubic metre (kg/m3) and the cgs unit of gram per cubic centimeter (g/cm3). There are 1000 kg/m3 in one g/cm3.

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The functional group or atoms needed to be present in the R-groups for hydrophobic interactions to occur between two amino acids are non-polar R-groups with hydrocarbon chain or rings.

Hydrophobic interaction are explains relation between water and low water soluble molecules. It describes the tendency of the non-polar groups to collect in any water solution.

Hydrophobic interactions happens among the non polar R-groups in the tertiary structure of amino acid.

The R groups are of varying size, shapes and charges. Hydrophobic interactions are important for tertiary structure of an amino acid, in which amino acids with non-polar R-groups join together on the inner side of protein, which leaves hydrophilic part on the outside.

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The charges are;

A charge is a specie that has a positive or a negative charge. We know that in chemistry, an atom could acquire a charge by the loss or gain of an electron. We now want to see the kind of charge that is formed from the spices as shown in the question.

Thus, according to the groups that the elements belong;

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As mixed acids continue to be catabolized to produce the neutral product, the methyl red test is used to gauge the pH shift from 4.4 to 6.0.

The pH scale is used to determine an aqueous solution's acidity or basicity. Historically, pH stood for "potential of hydrogen" (or "power of hydrogen"). In comparison to basic or alkaline solutions (solutions with higher concentrations of H+ ions), acidic solutions have lower pH values measured.

The hydrogen ion concentration in the solution is inversely proportional to the pH scale's logarithmic scale. The origin of the pH scale can be traced to a collection of standard solutions whose pH has been established by consensus on a global scale. Utilizing a concentration cell with transference, the primary pH standard values are computed by measuring the potential difference between a hydrogen electrode and a standard electrode, such as the silver chloride electrode.

Methyl red is a pH indicator with a pKa of 5.1; it is red at pH values below 4.4, yellow at pH values over 6.2, and orange at pH values in the middle. As potential boosters of the sonochemical annihilation of chlorinated hydrocarbon contaminants, murexide and methyl red are being studied.

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We must start with 368.82 grams of Al to produce 6.83 mol of [tex]Al_{2} O_{3}[/tex] .

The balanced reaction for the equation as follows:

[tex]4Al + 3O_{2}[/tex] ⇒ [tex]2Al_{2} O_{3}[/tex]

As we can see that 4 moles of Al reacts with 3 moles of [tex]O_{2}[/tex] to produce 2 moles of [tex]Al_{2} O_{3}[/tex], which means 108 grams of Al reacts with 96grams of [tex]O_{2}[/tex] to produce 204 grams of [tex]Al_{2} O_{3}[/tex].

Now,

2 mol of [tex]Al_{2} O_{3}[/tex] react with 108 grams of Al

So,

6.83 mol of [tex]Al_{2} O_{3}[/tex] react with = [tex]\frac{108}{2} *6.83[/tex] grams of Al

6.83 mol of [tex]Al_{2} O_{3}[/tex] react with = 368.82 grams of Al

Therefore, we must start with 368.82 grams of Al to produce 6.83 mol of [tex]Al_{2} O_{3}[/tex] .

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A total of three ions(particles) would be liberated when one formula unit of magnesium bromide is dissolved in water.

Magnesium bromide is an ionic compound, which when dissolved in water would completely ionize to give the magnesium and bromide ions as per the reaction,

MgBr2(aq) ----------> Mg2+(aq) + 2Br- (aq)

Each unit of magnesium bromide gives one magnesium ion and two bromide ions, So a total of three ions(particles) would be liberated when one formula unit of magnesium bromide is dissolved in water.

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Oliver's science project consists of six sealed and labeled containers. he challenges his classmates to identify pure substances versus mixtures and in that sugar is pure substance and air, smog, chocolate milk, coffee this are mixture substance

Here from above given data six sealed containers in that six containers sugar is pure substance because pure substance is a single kind of matter that cannot be separated into other kind of matter by any physical means called pure substance and sugar is pure and has a definite and constant composition, where air, smog, chocolate milk, coffee this are mixture substance because a mixture is a physical composition of two or more pure substances in which each substances retain its own chemical identity called mixture.

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The S6 (S2n) axis, which coincides with the C3 axis, and staggered ethane both have incorrect rotation axes. Cn stands for the correct rotation's 360/n-degree rotation about the axis. The C5 primary rotation axis of eclipsed ferrocene has five C2 axes that are perpendicular to it. S10 has an incorrect rotating axis.

With the chemical formula C 2H 6, ethane is an organic chemical substance. Ethane is a colourless and odourless gas at ordinary temperature and pressure. Fe(C5H5)2 is the formula for the organometallic compound ferrocene. The molecule is a complex made up of a core iron atom and two cyclopentadienyl rings.

The S6 (S2n) axis, which coincides with the C3 axis, and staggered ethane both have incorrect rotation axes. Ferrocene has an S10 incorrect rotation axis and is staggered. Ethane that is staggered belongs to the D3d point group. Cn stands for the appropriate rotation in staggered ethane, which is rotation about axis by 360/n degrees. The C5 primary rotation axis of eclipsed ferrocene has five C2 axes that are perpendicular to it. It belongs to the D5d point group as a result.

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The mass of chlorine required to react with 10.0 g of sodium metal to produce sodium chloride is 15.26 g.

The balanced chemical reaction is :

           2Na + Cl₂ → 2NaCl

Given data :

Mass of sodium = 10.0 g

Number of moles of Na -

Number of moles =  Given mass  

                                    Molar mass

Number of moles = 10.0 g = 0.43 mol

                                  23 g

Comparing moles of Na and Cl₂ from the balanced chemical equation,

                                            Na        :        Cl₂

                                             2          :         1

                                             0.43     :         1 x 0.43 = 0.215 mol

                                                                   2

Mass of chlorine gas :

          (molar mass of chlorine = 71 g)

Mass of chlorine = number of moles x molar mass

Mass = 0.215 mol x 71 g/mol

          = 15.26 g

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The catalyst for catalysing the hydrogenation of an unsaturated hydrocarbon is H2/Pt. A saturated hydrocarbon called an alkane, which is the main result, is produced when hydrogen atoms are added across a double or triple bond in the hydrocarbon.

A significant product is what?

The more stable and so more likely to develop main product of a reaction would be. One example would be the electrophilic addition of propane to HBr.

The catalyst for catalysing the hydrogenation of an unsaturated hydrocarbon is H2/Pt. A saturated hydrocarbon called an alkane, which is the main result, is produced when hydrogen atoms are added across a double or triple bond in the hydrocarbon.

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Carbon-12: with 6 protons and 6 neutrons and an atomic mass of 12.

The triple-alpha process, which creates carbon-12 in stars, accounts for its abundance, which accounts for 98.93% of the element carbon on Earth. Carbon-12 (12C) is the more abundant of the two stable isotopes of carbon (carbon-13 is the other). Since carbon-12 is used as the reference point to calculate the atomic masses of all other nuclides, its atomic mass is 12 daltons by definition, which makes it particularly significant. Six protons, six neutrons, and six electrons are found in carbon-12.

A resonant, excited, spinless form of carbon-12 is known as the Hoyle state. In 1954, Fred Hoyle predicted that it would exist. It is created using the triple-alpha process.

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0.095grams of KOh is needed to neutralize 12.6 ml of 0.14m HCl in stomach.

Chemical reaction:

HCl + KOH → KCl + H2O

Moles HCl = molarity x volume

Moles HCl = 0.14 M x .00126 L

Moles HCl = 0.0017 moles

Calculate moles of KOH

For 1 mol of KOH, we need 1 mole of HCl to produce 1 mol of KOH and 1 mole of H2O

For 0.0017moles of HCl, we need 0.0017 moles of KOH.

Calculate the mass of KOH

Mass of KOH = moles x molar mass

Mass of KOH = 0.0017moles x 56.1 g/mol

Mass of KOH = 0.095g

Hence, 0.095 grams of KOH are needed to neutralize 12.6 mL of 0.14 M HCl in stomach acid.

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LiAlH₄ (LAH) cannot be used to convert carboxylic acids to the corresponding aldehydes because RCOOH is reduced to RCH₂OH.

An organic molecule with the functional group RCH=O is known as an aldehyde. The functional group itself can be categorized as either a formyl group or an aldehyde.

Only when the correct reaction conditions are present in the reaction do specific organic reagents work as intended. For instance, only in the presence of a certain catalyst like Ni or Pt will hydrogen operate as a hydrogenating agent.

Powerful reducing agent LAH (lithium aluminum hydride) is the provided reagent. In the presence of carboxylic acids, it produces equivalent alcohols rather than aldehydes. The conversion of carboxylic acids to their equivalent aldehydes cannot be accomplished using it.

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The complete question is mentioned below:

LiAlH₄ ( LAH ) cannot be used to convert carboxylic acids to the corresponding aldehydes because:

a) LAH is not sufficiently reactive.

b) RCOOH is converted into RCOOLi.

c) RCOOH is reduced to RCH₂OH

d) RCOOH is reduced to RCH₃

e) RCOOH is converted into R₂C = O

The negative charge on each oxygen of the carbonate ion is -0.67 among the given options.

In this problem, when we look at the carbonate ion, firstly we need to look at how much negative charge is carried on the oxygen. Carbonate ion, (CO₃)²⁻ has two negative charges and there are three oxygen. So, -0.67 is the charge on each oxygen of carbonate ion.

Since, there are three oxygen in a carbonate ion, charge is divided as -

                   O                   O⁻                 O                  O⁻

                   ║                    |                    ║                   |

                   C          ↔      C        ↔       C     →          C

                 /    \                /    \\              /    \              /   \

              ⁻O     O⁻       ⁻ O     O         ⁻O    O⁻       ⁻O    O⁻

Negative charge for each oxygen will be -

-2/3, because two negative charges are divided by 3 oxygen.

Therefore, negative charge on each oxygen = -2/3 = -0.67

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Molar Mass, Molecular Weight and Elemental Composition Calculator ; Carbon, C · 12.0107, 4, 52.1710 ; Hydrogen, H · 1.00794, 6, 6.5673.

The mass of a sample of a chemical compound is divided by the quantity of that substance, or the number of moles in the sample, measured in moles, to obtain the compound's molar mass in chemistry.  

In contrast to molecular properties, a substance's molar mass is a bulk property. The compound is present in many different forms, each with a different mass as a result of the isotopes. The molar mass is the average of these masses. The molar mass is most frequently calculated using the standard atomic weights and is a function of the relative abundance of the constituent atoms' isotopes on Earth. It is thus a terrestrial average. In order to convert between a substance's mass and its amount, the molar mass is the suitable unit.

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1.  The empirical formula is ZnI₂.

2.  Balanced chemical equation for the reaction between zinc and iodine to form zinc iodide.

                   Zn + 2I → ZnI₂

3.  To find empirical formula, we have to do following steps.

    Step 1: Write given atoms.

    Step 2: Write given masses of corresponding  atoms.  

    Step 3: In next step atomic masses are written respectively.

    Step 4:Number of moles is calculated using,

              Number of Mole= Given mass/Molecular mass

    Step 5: Mole ratio is obtained by dividing with smallest mole.

Empirical formula of given problem is H₂O.

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Answer:

The Lewis dot structure for H is H, while the Lewis dot structure for He is He. The difference is due to the different number of valence electrons in each atom. H has one valence electron, while He has two valence electrons.

Explanation:

The explanation for this is that, according to the octet rule, atoms will tend to form bonds until they have eight valence electrons around them. H only has one valence electron, so it can only form one bond. He, on the other hand, has two valence electrons, so it can form two bonds.

Using standard reduction potentials from the aleks data tab, calculate the standard reaction free energy for the following redox reaction.

The standard Gibbs free energy for the given redox reaction is -106 kJ/mol.

Let's consider the following redox reaction.

10 Cl⁻(aq) + 2 MnO₄⁻(aq) + 16 H⁺(aq) ⇒ 5 Cl₂(g) + 2 Mn²⁺(aq) + 8 H₂O(l)

We can identify both half-reactions with their respective standard reduction potentials (E°red).

Cathode: 2 MnO₄⁻ + 16 H⁺ + 10 e⁻ ⇒ 2 Mn²⁺ + 8 H₂O  E°red = 1.51 V

Anode: 10 Cl⁻ ⇒ 5 Cl₂ + 10 e⁻                                        E°red = 1.40 V

With this information, we will calculate the standard cell potential (E°cell).

What is the standard cell potential?

The standard cell potential is the potential difference between the cathode and anode.

E°cell = Ered,cathode - E°red,anode = 1.51 V - 1.40 V = 0.11 V

What is the standard Gibbs free energy?

The standard Gibbs free energy (ΔG°) is a thermodynamic potential that can be used to calculate the maximum reversible work that may be performed by a thermodynamic system under standard conditions.

It can be calculated using the following expression

ΔG° = - n × F × E°cell

ΔG° = - 10 mol × (96,485 J/V.mol) × 0.11 V × (1 kJ/1000 J) = -106 kJ/mol

where,

n are the moles of electrons exchanged.

F is Faraday's constant.

The standard Gibbs free energy for the given redox reaction is -106 kJ/mol.

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Answer:

With an 18-carbon backbone, stearic acid is a saturated long-chain fatty acid.

What is Stearic Acid?

With an 18-carbon chain, stearic acid is a saturated fatty acid. Octadecanoic acid is the substance's IUPAC name. It has the chemical formula C₁₇H₃₅CO₂H and is a waxy solid. The word "stear," which means tallow in Greek, is where it gets its name. Stearates are the names for the salts and esters of stearic acid. The second most prevalent saturated fatty acid in nature after palmitic acid is stearic acid, which serves as its ester. [11] Stearin is the triglyceride produced when three molecules of stearic acid are combined.

Explanation:

Animal fat contains more stearic acid than vegetable fat does. The foods cocoa butter and shea butter are the notable exceptions because they contain stearic acid (as a triglyceride).

In terms of its biosynthesis, acetyl-CoA contributes two-carbon building blocks to the fatty acid synthesis machinery, which converts carbohydrates into stearic acid.

The triglycerides in fats and oils are saponified with hot water to produce stearic acid. After that, the resulting mixture is distillated.

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The pH of solution will reach upto 4.22 after bringing the solution to 1L.

The reaction is HCOOH + NaOH  ---->  HCOONa + H2O

What is pH?

Since the pH of a substance is essentially a measurement of the concentration of hydrogen ions (or protons), the letters pH stand for potential of hydrogen. Biologist Sren Peter Lauritz Srensen created the pH scale in 1923. (1868-1969).

Potential of Hydrogen is what pH is formally known as.The definition of pH as the quantity of hydrogen is given as the negative logarithm of the concentration of H+ ions. The hydrogen ion concentration in a solution is described by the pH scale, which also determines how acidic or basic a solution is.

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