Answer:
SF2(aq) → S²⁺(aq) + 2F-(aq)
Explanation:
The sulfur difluoride, SF2, dissolves in water because the differences in electronegativities are considerable (3.98 for Fluorine and 2.58 for S) doing the F-S bond polar. As water is a polar solvent will dissolve the SF2 as follows:
SF2(aq) → S²⁺(aq) + 2F-(aq)As Fluorine has a > electronegativity than S, the Fluorine will be negative and S will be positive. Also, all halogen ions has a charge of -1.
Consider an acid-base titration in which the base is dispensed from a burette into a flask containing an acid. If any drops of the base adhere to the inner walls of the flask, but do not actually mix with the solution, the calculated acid concentration would be
Answer:
Higher than the actual value
Explanation:
Titration is a volumetric process in which a known volume of solution is dispensed from a burette to react with a known volume of solution in a conical flask.
When acid-base titration is carried out in such a way that the base is in the burette and the acid is in the conical flask and drops of the base adhere to the inner walls of the flask, but do not actually mix with the solution, the calculated acid concentration would be higher than the actual value.
This is because;
From CA= CBVBnA/VAnB
When VB(volume of base) that reacted is lower than the actual volume recorded, then the calculated volume of CA(concentration of acid) is much higher than the actual value since drops of the base adhere to the inner walls of the flask.
What is the molarity of an HCl solution if 43.6 mL of a 0.125 M NaOH solution are needed to titrate a 25.0 mL sample of the acid according to the equation below (show your calculations)? NaOH(aq) + HCl(aq) → H2O(l) + NaCl(aq)
Answer: The molarity of an HCl solution is 0.218 M if 43.6 mL of a 0.125 M NaOH solution are needed to titrate a 25.0 mL sample of the acid.
Explanation:
Given: [tex]V_{1}[/tex] = 43.6 mL, [tex]M_{1}[/tex] = 0.125 M
[tex]V_{2}[/tex] = 25.0 mL, [tex]M_{2}[/tex] = ?
Formula used to calculate the concentration of acid is as follows.
[tex]M_{1}V_{1} = M_{2}V_{2}[/tex]
Substitute the values into above formula.
[tex]M_{1}V_{1} = M_{2}V_{2}\\0.125 M \times 43.6 mL = M_{2} \times 25.0 mL\\M_{2} = 0.218 M[/tex]
Thus, we can conclude that the molarity of an HCl solution is 0.218 M if 43.6 mL of a 0.125 M NaOH solution are needed to titrate a 25.0 mL sample of the acid.
The molarity of the HCl solution used in the neutralization reaction has been 0.218 M.
The reaction of NaOH with HCl has been a neutralization reaction. The resultant will be salt and water.
In the reaction the molarity can be calculated as:
Molarity of HCl [tex]\rm[/tex][tex]\times[/tex] Volume of HCl = Molarity of NaOH
Given,
The volume of HCl solution = 25 ml
Molarity of NaOH = 0.125 M
Volume of NaOH solution = 43.6 ml
Substitute the values in the equation:
Molarity of HCl [tex]\times[/tex] 25 = 0.125 [tex]\times[/tex] 43.6
Molarity of HCl [tex]\times[/tex] 25 = 5.45
Molarity of HCl solution = [tex]\rm \dfrac{5.45}{25}[/tex]
Molarity of HCl solution = 0.218 M
The molarity of the HCl solution used in the neutralization reaction has been 0.218 M.
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0.300 moles of sodium nitrite are needed for a reaction. The solution is 0.450 M. How many mL are needed
Answer:
The solution is 0.450 M. How many mL are needed?
- 0.667 mL
Explanation:
The energy needed to collapse the H-bonding of ice is _____.
it depends on the widths of the recesses, and if it is causing the shelf to fracture and collapse into the sea, then a massive iceberg could be called from the life she,f and the ice shelf are way more important because it holds it up
Which of the following can be determined from the frequency of a light wave?
O A. The height of the wave
O B. The direction of the wave
O C. The source of the wave
O D. The energy of the wave
I Am Thinking A.
Answer:
The answer is d because the light is energy of wave
The frequency of a light wave can be determined
The energy of the wave.So, option D is correct one.
What is frequency?
The number of occurrence of repeating events per unit time is called frequency.The units of frequency is per second or Hertz(Hz).The frequency is used to calculate energy of light .The frequency is directly proportional to the energy. So, if frequency increases the energy also increases.Energy equation,
[tex]E= hv[/tex]
where,
[tex]E[/tex] = Energy of light
[tex]h[/tex]= Planks constant
[tex]v[/tex] = Frequency of wave.
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Calculate the number of ATOMS in 1.0 mole of O2. blank x 1024
Answer:
6.023*10^23........ .......
Balance the following reactions and identify the species that have been oxidized and the species that have been reduced.
CL2 +I- -------------> I2 +CL-
WO2 + H2 ---------------> W + H2O
CA + H2O -----------------> H2 + CA(OH)2
AL+ O2 --------------------> AL2O3
Answer:
Balance the following reactions and identify the species that have been oxidized and the species that have been reduced.
CL2 +I- -------------> I2 +CL-
WO2 + H2 ---------------> W + H2O
CA + H2O -----------------> H2 + CA(OH)2
AL+ O2 --------------------> AL2O3
Explanation:
Oxidation is the process where an atom loses electrons.
During oxidation, the oxidation number of the atom increases.
Reduction is the process where an atom gains electrons.
During reduction, the oxidation number of the atom decreases.
The balanced chemical equations for the given reactions are shown below:
[tex]Cl_2 +2I^- -> I_2 + 2Cl^-[/tex]
Iodine undergoes oxidation and chlorine undergoes reduction.
[tex]WO_2 +2 H_2 -> W+ 2 H_2O\\[/tex]
In this reaction, W (tungsten) undergoes reduction and hydrogen undergoes oxidation.
[tex]Ca+2 H_2O ->H_2+Ca(OH)_2\\[/tex]
Ca undergoes oxidation and hydrogen undergoes reduction.
[tex]4Al+3O_2->2Al_2O_3\\[/tex]
Al undergoes oxidation and oxygen undergoes reduction.
Give your familiarity for following terms
1. roasting 2. smelting 4. zone refining 5. polling
Answer:
The roasting process is a delicate combination of art and science . Roasters are familiar with how the beans look and the smells Well, familiarity with the machine makes things much easier to predict, but the best way is to do many different tests .Well, familiarity with the machine makes things much easier to predict, but the best way is to do many different tests.Smelting is a process of applying heat to ore in order to extract a base metal. It is a form of extractive metallurgy. It is used to extract many metals from their ores, including silver, iron, copper, and other base metals.In zone refining, solutes are segregated at one end of the ingot in order to purify the remainder, or to concentrate the impurities. For example, in the preparation of a transistor or diode semiconductor, an ingot of germanium is first purified by zone refining. In zone refining, solutes are segregated at one end of the ingot in order to purify the remainder, or to concentrate the impurities. ... For example, in the preparation of a transistor or diode semiconductor, an ingot of germanium is first purified by zone refining.Polling is the process where the computer or controlling device waits for an external device to check for its readiness or state, often with low-level hardware. For example, when a printer is connected via a parallel port, the computer waits until the printer has received the next character.Explanation:
hope it heloed
Draw the skeletal structure for: (E)-hept-5-en-2-one
Answer:
Draw the skeletal structure for: (E)-hept-5-en-2-one
Explanation:
The root word hept indicates that the given compound has seven carons in its longest chain.
-en- primary suffix indicates that the compound has one double bond in it.
2-one indicates that the compound has -C=O bond in the second carbon.
The prefix (E) indicates that the highest priority groups are on the opposite direction of the double bond.
The structure of the given molecule is:
A physical chemist measures the temperature inside a vacuum chamber. Here is the result.
T= - 35.903°C
Convert T to SI units.
This is an acronym of the word Systeme International in French. Its International System of Units (SI) is a metric system that would be universally acknowledged as a measurement standard, and the further discussion can be defined as follows:
SI units play an important function in research and innovation in science and technology. In this, the temperature will be measure in the kelvin.Conversion [tex]^{\circ} \ to \ K[/tex]:
let,
[tex]\to 0^{\circ}\ C + 273.15 = 273.15\ K\\\\[/tex]
So,
[tex]\to -35.903+273.15=237.247\ K[/tex]
Therefore, the final answer is "237.247".
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Classify each of the following as a strong acid or a weak acid and indicate how each should be written in aqueous solution. Classify ... In solution this acid should be written as: weak 1. hydrocyanic acid H3O CN- _______ 2. hydrobromic acid
Answer:
HCN, weak acid
H⁺, Br⁻, strong acid
Explanation:
Hydrocyanic acid is a weak acid, according to the following equation.
HCN(aq) ⇄ H⁺(aq) + CN⁻(aq)
Thus, it should be written in the undissociated form (HCN).
Hydrobromic acid is a strong acid, according to the following equation.
HBr(aq) ⇒ H⁺(aq) + Br⁻(aq)
Thus, it should be written in the ionic form (H⁺, Br⁻).
Draw 2,3-dichloro octane
Answer:
Hi friend
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Which of the following statements correctly explains why bromination reactions are more selective than chlorination reactions.
a. bromine radical is less stable than chlorine radical, so it is more reactive and less choosy
b. bromine radical is more stable than chlorine radical, so it is more reactive and less choosy
c. bromine radical is more stable than chlorine radical, so it is less reactive and more choosy
d. bromine radical is less stable than chlorine radical, so it is less reactive and more choosy
e. relative radical stability is 3' radicals > 2" radicals> 1 radicals when bromine radicals snatch hydrogens from alkanes, but when chlorine radicals snatch hydrogens the resulting alkyl radical stability is 3 radicals < 2 radicals< 1' radicals
Answer: A bromine radical is more stable than chlorine radical, so it is less reactive and more choosy.
Explanation:
A chlorine atom being more electronegative in nature is able to attract a hydrogen atom more readily towards itself as compared to a bromine atom.
Since bromine is less electronegative in nature so bromine will be more selective as a hydrogen abstracting agent. As a result, bromine radical is more stable in nature than chlorine radical.
Thus, we can conclude that bromine radical is more stable than chlorine radical, so it is less reactive and more choosy.
g Consider two different liquids at atmospheric pressure: hexane and water. Hexane has a higher vapor pressure than water. As a result, the temperature at which hexane will boil will be [ Select ] water and its vapor pressure when it is boiling will be [ Select ] water when water is boiling.
Answer:
Lower than
Higher than
Explanation:
The vapour pressure and boiling point of liquids are inversely related. Thus, the higher the vapour pressure of a liquid, the lower it's boiling point. Lower vapour pressure implies that the liquid is easily converted into vapour phase.
If hexane has a higher vapour pressure than water then its boiling point is lower than that of water and its vapor pressure when it is boiling will be higher than water when water is boiling.
1. Arrange the following groups in order of decreasing priority that would allow you to determine E/Z, or R/S. Provide a string of letters (e.g. abcd) as an answer with the highest priority listed first, lowest priority last:
a) -CH3 b) -CH2OH c) -CH2NH2 d) -CH2BR
2. Arrange the following groups in order of decreasing priority that would allow you to determine E/Z, or R/S. Provide a string of letters (e.g. abcd) as an answer with the highest priority listed first, lowest priority last:
a) -F b) -CH2OH c) -CHO d) -CH3
1) The order of decreasing priority would allow determining E/Z or R/S is "dbca".
2) The order of decreasing priority would allow determining E/Z or R/S is "acbd".
What is absolute configuration?Absolute configuration can be described as to the spatial arrangement of atoms within a chiral molecular entity. Absolute configuration in organic molecules, where carbon is bonded to four different substituents.
The absolute configuration has used a set of rules to describe the relative positions around the chiral center atom. The most common labeling method is the descriptors R or S where R and S refer to Rectus and Sinister.
The group with the highest atomic number will get the highest priority and the group with the lowest atomic number substituents will get the lowest priority. Therefore, the order of priority is -CH₂Br > -CH₂OH > -CH₂NH₂ > -CH₃.
Therefore, the order of priority for the second part is -F > -CHO > -CH₂OH > -CH₃.
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What Is The Name For CH3(CH2)4CH3
Answer:
hexane
I hope it's helps you
Write the balanced half-equations for silver + oxygen= silver oxide:
Answer: The balanced half-equations for silver + oxygen= silver oxide are:
Oxidation-half reaction: [tex]Ag \rightarrow 2Ag^{+} + 2e^{-}[/tex]
Reduction-half reaction: [tex]O_{2} + 2e^{-} \rightarrow 2O^{-}[/tex]
Explanation:
The word equation is as follows.
silver + oxygen = silver oxide
In terms of chemical formulas this equation can be written as follows.
[tex]Ag + O_{2} \rightarrow Ag_{2}O[/tex]
The removal on electron(s) from an atom, ion or molecule in a chemical reaction is called oxidation.
The gain of electron(s) by an atom, ion or molecule in a chemical reaction is called reduction.
Hence, half-reaction equations for the given reaction is as follows.
Oxidation-half reaction: [tex]Ag \rightarrow 2Ag^{+} + 2e^{-}[/tex]
Reduction-half reaction: [tex]O_{2} + 2e^{-} \rightarrow 2O^{-}[/tex]
As the number of atoms participating in the reaction are equal. Hence, the half-equations are balanced.
Thus, we can conclude that the balanced half-equations for silver + oxygen = silver oxide are:
Oxidation-half reaction: [tex]Ag \rightarrow 2Ag^{+} + 2e^{-}[/tex]
Reduction-half reaction: [tex]O_{2} + 2e^{-} \rightarrow 2O^{-}[/tex]
Using any data you can find in the ALEKS Data resource, calculate the equilibrium constant k at 25.0 celsius for the following reaction.
6Cl2(g)+2Fe2O3(s)----->4FeCl3(s)+3O2
Round answer to 2 significant digits.
Answer:
Explanation:
From the given reaction:
[tex]6Cl_{2(g)}+2Fe_2O_{3(s)} \to 4FeCl_{3(s)}+3O_2[/tex]
From the Gibbs Free Energy table at standard conditions, the value of each compound is as follows:
[tex]G_f^0 \ of \ Cl_2 = 0 \ KJ/mol[/tex] [tex]G_f^0 \ of \ Fe_2O_3 = -742.24 \ KJ/mol[/tex]
[tex]G_f^0 \ of \ Fe_2Cl_3 = -334.05 \ KJ/mol[/tex] [tex]G_f^0 \ of \ O_2 = 0 \ KJ/mol[/tex]
Now, the standard Gibb's Free energy for the given reaction can be estimated as follows:
[tex]\mathtt{\Delta G^0 = (4 *G_f^0(FeCl_3) +3*G_f^0(O_2)) - (6*G_f^0 (Cl_2) +2*G_f^0(Fe_2O_3))}[/tex]
[tex]\mathtt{\Delta G^0 = (4 *(-334.05) +3*(0)) - (6(0) +2(-742.24))}[/tex]
[tex]\mathtt{\Delta G^0 = 148.28 \ kJ/mol}[/tex]
using the following formula:
[tex]\mathtt{\Delta G^0 =-RTIn K_{eq}}[/tex]
the equilibrium constant can be determined as:
[tex]\mathtt{ In K_{eq} =\dfrac{\Delta G^0 }{-RT}}[/tex]
[tex]\mathtt{ In K_{eq} =\dfrac{148.28*10^3 J/mol }{-(8.314 \ J/k mol )*298 \ K}}[/tex]
[tex]\mathtt{ In K_{eq} =-59.85}[/tex]
[tex]\mathtt{ K_{eq} =e^{-59.85}}[/tex]
[tex]\mathtt{ K_{eq} =1.0*10^{-26}}[/tex] to 2 significant figures.
in a breaker of water ,the water -water bonds can properly be called
Answer:
LICK
Explanation:
A student measured the gram weight of a metal object to be 5.88g. According to the supplier the object weighs 5.97g. What is the error in the student's measurement?
A. -0.09
B. +0.09
Answer:
–0.09
Explanation:
From the question given above, the following data were obtained:
Measured value = 5.88 g
Actual value = 5.97 g
Error =?
The error in the student's measurement can be obtained as follow:
Error = Measured value – Actual value
Error = 5.88 – 5.97
Error = –0.09
Therefore, the error in the student's measurement is –0.09
list four energy resources
Answer:
Nuclear
Solar
Wind
Hydro
Geo-Thermal
Explanation:
Solar energy from the sun.Geothermal energy from heat inside the earth.Wind energyBiomass from plants.hope it helps
stay safe healthy and happy....An ionic compound contains an unknown ion X and has the formula X3N2. Ion X contains 10 electrons. Write down the chemical symbol of X?
Answer:
Mg3N2
Explanation:
it would be magnesium as it would loss to electron so it would have 10 electron. you can see in the picture above .
hope this helps :)
ELECTROLYSIS OF MOLTEN NaCl IS DONE IN A DOWNS CELL OPERATING AT 7.0 VOLTS AND 4.0X10^4A. HOW MUCH Na(s) AND Cl2(g) CAN BE PRODUCED IN 8 HOURS IN SUCH A CELL?
Answer:
Mass of sodium produced = 2.74 × 10⁵ g of Na
Mass of chlorine produce = 4.24 × 10⁵ g of Cl₂
Explanation:
In the electrolysis of molten NaCl as described above, the quantity of charge used is given by the formula, Q = I × t
Where I isnthe current passed in amperes and t is time in seconds.
Q = 4.0 × 10⁴ A × (8 × 60 × 60) s = 1.152 × 10⁹ C
Equation for the discharge of sodium is; Na+ + e- ---> Na (s)
One mole of electrons is required to discharge one mole of Na
One mole of electron = 1 faraday = 96500 C
One mole of Na has a mass of 23 g
96500 C produces 23 g of Na
1.152 × 10⁹ C will produce 23 g × 1.152 × 10⁹ C / 96500 C = 2.74 × 10⁵ g of Na
Equation for the discharge of chlorine gas is; 2 Cl- ---> Cl₂(g) + 2e-
Two mole of electrons are required to discharge one mole of chlorine gas
Two moles of electron = 2 faraday = 2 × 96500 C = 193000
One mole of Cl₂ has a mass of 71 g
193000 C produces 71 g of Cl₂
1.152 × 10⁹ C will produce 71 g × 1.152 × 10⁹ C / 193000 C = 4.24 × 10⁵ g of Cl₂
The amount of Na produced is 274551 g and the amount of Cl₂ produced is 423763.5 g.
Current passed through the cell = [tex]4.0\times10^4 A[/tex]
Time = 8 Hours
We have to calculate the amount of Na and [tex]Cl_2[/tex] produced in 8 hours in the downs cell.
What is a down cell?The Downs process is an electrochemical method for the commercial preparation of metallic sodium, in which molten NaCl is electrolyzed in a special apparatus called the Downs cell.
The total charge passed through the cell is calculated by the given formula as
Charge(Q) = Current(I) × time(t)
Q = [tex]4.0\times10^4 A \times t[/tex]
[tex]t = 8 \times 60\times 60[/tex] sec
t = 28800 sec
Q = [tex]4.0\times10^4 A \times 28800[/tex] sec
Q = [tex]115200\times 10^4 A\ sec[/tex]
We know that, Ampere = Coulombs per sec
Q = [tex]115200\times 10^4\ C[/tex]
1 mol of electrons 96500 C charge
Therefore, the number of mols of electrons carries this [tex]115200\times 10^4\ C[/tex] charge = [tex]\frac{115200\times10^4}{96500}[/tex] = 1.1937 × 10⁴ = 11937 mol electrons
In the Down's cell
Half cell reactions are:
Reduction half-reaction: [tex]2Na^+(aq)+2e^- \to 2Na(s)[/tex]
Oxidation half-reaction: [tex]2Cl^-(aq)\to Cl_2(g) + 2e^-[/tex]
We know that no. of moles = [tex]\frac{given \ mass}{molar \ mass}[/tex]
Molar mass of Na = 23 g/mol
The mass of Na formed = 11937 mol × 23 g/mol = 274551 grams
The molar mass of Cl₂ = 71 g/mol
The mass of Cl₂ = [tex]\frac{11937}{2}\times 71 = 423763.5 \ grams[/tex]
Hence, the amount of Na produced is 274551 g and the amount of Cl₂ produced is 423763.5 g.
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A Bronsted-Lowry acid is defined as a substance that ________. A Bronsted-Lowry acid is defined as a substance that ________. increases Ka when placed in H2O increases [OH-] when placed in H2O acts as a proton donor acts as a proton acceptor decreases [H ] when placed in H2O
Answer: A Bronsted-Lowry acid is defined as a substance that acts as a proton donor.
Explanation:
A substance that is able to donate a proton or hydrogen ion to another substance is a Bronsted-Lowry acid.
For example, HCl is a Bronsted-Lowry acid as it dissociates to give a hydrogen ion.
[tex]HCl \rightleftharpoons H^{+} + Cl^{-}[/tex]
Thus, we can conclude that a Bronsted-Lowry acid is defined as a substance that acts as a proton donor.
Which one of the following compounds does NOT obey the "octet rule"?
LiF
BF3
H20
CBr4
Answer:
BF3
Explanation:
The octet rule describes atoms' preference and affinity for having eight (8) electrons in their valence shell. Whenever an atom is encircled by eight(8) electrons, it forms a stable configuration. This octet can be composed of its' own electrons as well as some shared electrons. In the periodic table, only the s-block and p-block electrons are considered for the octet rule.
However, out of the given option, only BF3 does not comply with the octet rule: This is because the Bromine contains 2 lone pairs of electrons and 3 other shared bonded pairs of electrons with Flourine making a total of 10 electrons in the valence shell and which does not conform with the octet rule.
PLEASE HELP!!!
Explain the various factors that impact the solubility of substances in water.
(At least 4 sentences) :)
The various factors that impact the solubility of substances in water are - nature of solute and solvent, temperature, pressure and pH.
The solubility of substances in water is influenced by several factors:
Nature of the solute and solvent: The chemical properties of both the solute and the solvent play a significant role. Substances with similar polarities and intermolecular forces tend to dissolve more readily in water. Polar solutes, such as salts and sugars, dissolve well in polar solvents like water, whereas nonpolar solutes, like oils and fats, have low solubility in water.Temperature: In general, an increase in temperature enhances the solubility of solid solutes in water, as it provides more energy for the solute particles to overcome intermolecular forces and mix with the solvent. However, the effect of temperature on solubility can vary depending on the specific solute. For some solutes, such as gases, solubility decreases with increasing temperature.Pressure (for gases): The solubility of gases in water is influenced by pressure. According to Henry's law, the solubility of a gas in a liquid is directly proportional to the partial pressure of the gas above the liquid. Therefore, an increase in pressure generally leads to an increase in gas solubility in water.pH: The pH of the solution can impact the solubility of certain substances. For example, the solubility of acidic or basic compounds may change with varying pH levels.Learn more about Solubility, here:
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13. What would you expect the pH of an aqueous solution of tertiary bromide in water to be (acidic, neutral, or basic)
Answer:
oshfjidgshsjdh
Explanation:
918474828
In a pure metal, the electrons can be thought of as [ Select ] throughout the metal. Using molecular orbital theory, there [ Select ] an energy gap between the filled molecular orbitals and empty molecular orbitals. The [ Select ] orbitals are typically higher in energy and are mostly [ Select ] .
Answer:
Explanation:
In a pure metal, the electrons can be thought of as [concentrated] around atoms throughout the metal. Using molecular orbital theory, there [is ] an energy gap between the filled molecular orbitals and empty molecular orbitals. The [antibonding] orbitals are typically higher in energy and are mostly (filled]
Qual número atômico do ferro?
Answer:
The answer is Iron.
Explanation:
I hope this helps you out. Have a nice day!
The concentration ratio of conjugate acid to conjugate base for a 20 mM solution at pH 7.0 of an amino acid is 20:1.
Required:
a. What is the pK of the side chain?
b. What amino acid might this be?
Answer:
a. 8.3= pKa of the aminoacid
b. Cysteine
Explanation:
The pH of an acid can be obtained using the H-H equation:
pH = pKa + log [A-] / [HA]
Where pH is the pH of the buffer = 7.0
pKa is the pka of the conjugate acid = ?
[A-] / [HA] is the ratio between conjugate base and conjugate acid. As the ratio of conjugate acid to conjugate base = 20:1, the [A-] / [HA] = 1/20
Replacing:
7 = pKa + log 1/20
7 = pKa - 1.30
7+1.30 = 8.3 = pKa of the aminoacid
The only aminoacid with a side chain with pKa = 8.3 is:
Cysteine. Allowing its identification.
