Answer:
:)
Explanation:
The nucleus in biology is usually referring to that of
living cells found in organisms in which contains DNA whereas the nucleus in chemistry is usually referring to that of atoms in which contains subatomic particles such as the proton and neutron.
2. In a chemical reaction, what do we call the original substances?
3. In a chemical reaction, what do we call newly made substances?
4. What are the three common states of matter?
5. If the mass of all the reactants in a chemical reaction is 100g, what will the mass
of all the products be?
Answer:
2. Reactants
3. Products
4. Solid, Liquid, Gas
5. 100g
The density of a solid is 2.88 g/cm³. The dimensions are 3.2 cm by 1.8 cm by 3.0 cm. What is the mass of the solid?
Answer:
49.7664g
Explanation:
First, we define the formula for the density of a matter.
Density = Mass ÷ Volume
Rearranging the formula, to find mass, we have:
Mass = Density × Volume = 2.88 × (3.2 × 1.8 × 3) = 49.7664g
Take note of all the units,ensure all matches, otherwise, you might have to do some conversions.
Producing sodium chloride (table salt) is impractical and expensive. Sodium
chloride can be extracted from seawater. How could this be
done using a common renewable energy source?
For the harvesting of salt from seawater, solar energy is used. To evaporate seawater, solar energy is used. As the concentration of the salt increases, it crystallizes.
What is renewable source of energy?Renewable energy is defined as energy derived from natural sources that is replenished at a faster rate than it is consumed.
Sunlight and wind are two examples of such constantly replenishing sources. Renewable energy sources are plenty and are all around us.
Solar energy is utilized to get salt from seawater. Solar energy is used to evaporate seawater. The salt crystallizes as its concentration increases.
Thus, this way, salt extraction can be done using a common renewable energy source.
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A cup of coffee contains 87.2 mg of caffeine. how many grams is this?
Answer:
0.0872g
Explanation:
Since mg is smaller than g, you will have to multiply the mg by milli which is equal to 10⁻³.
87.2 × 10⁻³ = 0.0872 grams
A cup of coffee contains 87.2 mg of caffeine. The number of grams present in the cup of coffee is 0.0872g.
What are grams and milligrams?Grams and milligrams are the measurement units that measure the amount or quantity of matter. It measures the solid mass and the quantity of matter. It is the SI unit of mass. There are seven units of measurement.
These units are Length - meter (m), Temperature - kelvin (K), amount of substance - mole (mole), Luminous intensity - candela (cd), Electric current - ampere (A), Mass - kilogram (kg), Time - second (s).
Here the mass of caffeine is asked in grams, which are given in milligrams.
As we know, 1 gram is = 1000 milligrams.
0.0872g = 87.2 mg
Thus, the number of grams present in the cup of coffee is 0.0872g.
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3.
sublimation, condensation, evaporation,
boiling, melting, freezing
Classify the above processes into two
groups: heat taken in and heat given out
by the particles.
Answer:
sublimation:heat taken in
condensation:heat given out
evaporation:heat taken in
boiling:heat taken in
melting:heat taken in
freezing:heat given out
Processes listed can be classified into two groups based on whether heat is taken in or given out by the particles.Heat is taken in melting,evaporation, sublimation while heat is given out in boiling,condensation and freezing.
Heat taken in by the particles:
1. Sublimation: This process occurs when a substance changes from a solid directly to a gas without passing through the liquid phase. Heat is absorbed to break the intermolecular forces holding the particles in the solid phase.
2. Evaporation: This process happens when a liquid changes into a gas at temperatures below its boiling point. Heat is absorbed from the surroundings to overcome the intermolecular forces between the liquid particles.
3. Melting: Melting occurs when a solid substance changes into a liquid. Heat is absorbed to break the intermolecular forces holding the particles in the solid phase.
Heat given out by the particles:
1. Condensation: Condensation occurs when a gas changes into a liquid. Heat is released to the surroundings as the gas particles lose energy and come together to form liquid droplets.
2. Boiling: Boiling is the process where a liquid changes into a gas throughout its entire volume. Heat is released to the surroundings as the liquid particles gain energy and escape the liquid phase.
3. Freezing: Freezing is the process where a liquid changes into a solid. Heat is released to the surroundings as the liquid particles lose energy and arrange themselves into a regular pattern.
Thus, heat is taken in melting,evaporation, sublimation while heat is given out in boiling,condensation and freezing.
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How many ml of a 5.0 m solution of sodium borate must be added to a 200 ml solution of 50 mm boric acid in order for the ph to be 9.6?
4.6 ml of a 5.0 M solution of sodium borate must be added to a 200 ml solution of 50 mM boric acid in order for the pH to be 9.6.
Henderson–Hasselbalch equation for buffer solution:
pH = pKa + log(cs/ck)
pH = 9.6; pH of the buffer solution of sodium borate and boric acid
pKa = 9.24
log(cs/ck) = 9.6 - 9.24
log(cs/ck) = 0.36
cs/ck = 2.29; ratio of sodium borate and boric acid
nk = 0.05 M × 0.2 l
nk = 0.01 mol; amount of boric acid
Vs = 200 ml ÷ 100 × 2.29
Vs = 4.6 ml; volume of sodium borate
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What of the following of density is true. a density is measured in grams. density is mass per unit volume. density is measured is millimeters density is a chemical property
A hypothesis is _____
A: a law
B: an educated guess
C: a fact
D: always proven
I think it's the D because you should prove it
Refer to the graph you prepared and determine the following: Interpolation: The amount of hydrogen that would be produced by dropping 2.5 grams of zinc in 100 mL of sulfuric acid solution with th same concentration? mL
By interpolation, the volume of hydrogen gas produced is 800 mL.
What is the amount of hydrogen that would be produced by dropping 2.5 grams of zinc in 100 mL of sulfuric acid solution with the same concentration?The reaction between zinc granules and sulfuric acid solution to produce hydrogen gas is given by the equation below:
Zn (s) + H₂SO₄ → ZnSO₄ + H₂ (g)In the given reaction, zinc displaces hydrogen from solution to form zinc ions and hydrogen gas is evolved.
The volume of hydrogen gas evolved per unit time, and hence the reaction rate depends on the concentration of the sulfuric acid. The higher the concentration of the sulfuric acid, the greater the volume of hydrogen gas produced per unit time.
Considering the graph of the given volume of hydrogen produced against time for the reaction carried out by by dropping 2.5 grams of zinc in 100 mL of sulfuric acid solution with the same concentration;
By interpolation, the volume of hydrogen gas produced is 0.8 L or 800 mL.
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Nonpolar amino acid residues are typically found in the interior of globular proteins like trypsin. Which chemical force is most directly responsible?.
The chemical force most directly responsible in the given case is hydrophobic interactions.
The interactions between hydrophobes and water, or low water-soluble compounds, are illustrated by the hydrophobic interactions. Nonpolar hydrophobes often have a longer carbon chain than polar molecules and do not interact with the water molecules. By removing a peptide from the N terminus of trypsinogen, it can become trypsin, which allows a salt bridge to develop between the new N-terminal.
The trypsin "activation domain" undergoes a conformational shift in response to the development of this salt bridge, resulting in the establishment of the oxyanion hole and S1 binding site. Trypsinogen activation thus seems to be an illustration of protein folding influenced by electrostatic interactions. The activation domain receives 5 kcal/mol of stabilization energy through hydrophobic interactions with the Ile16 side chain.
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Calculate the mass fraction of sodium chloride in the solution if 20 g of it is dissolved in 300 ml of water.
Solve with explanation! Given: Solution:
The mass fraction of sodium chloride is 0.0625
What is the mass fraction of sodium chloride in the solution?The mass fraction of sodium chloride is the ratio of the mass of sodium chloride to the total mass of the solution.
The mass fraction of sodium chloride is determined as follows;
mass of sodium chloride = 20 g
mass of water = volume * densitydensity of water = 1 g/mL
volume of water = 300 mL
mass of water = 300 mL * 1 g/mL
mass of water = 300 g
total mass of solution = 20 + 300 = 320 g
mass fraction of sodium chloride = 20/320
mass fraction of sodium chloride = 0.0625
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which substance does not have a definite shape, color, or texture?
I believe gases do not have a definite shape, color, or texture.
A solid has definite volume and shape, a liquid has a definite volume but no definite shape, and a gas has neither a definite volume nor shape
So the answer is a gas
Calculate the number of atps that will be made in the complete oxidation of arachidonic acid.
The number of ATPs that will be made in the complete oxidation of arachidonic acid is 155.
There are 9 β-oxidation cycles for complete oxidation of arachidonic acid (it has 20 carbon atoms).
Arachidonic acid has 20 carbon atoms and four double bonds (see picture below).
One β-oxidation (beta-oxidation) cycle produces 1 NADH, 1 FADH2, and 1 acetyl CoA (sea the picture below).
For 9 cycles: 9 NADH, 9 FADH2, and 10 acetyl CoA.
NADH and FADH2 enter Electron Transport System (ETS) cycle to generate 3ATP and 2ATP respectively.
Acetyl CoA enter into tricarboxylic acid cycle (TCA) and each CoA gives 12 ATP.
9 NADH = 9 x 3 = 27 ATP
9 FADH2 = 9 x 2 = 18 ATP
10 acetyl-CoA = 10 x 12 = 120 ATP
Net yield of ATP = 27 ATP + 18 ATP + 120 ATP -2 ATP - 8 ATP (it has four double bonds)
Net yield of ATP = 155 ATP
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Are Alkaline Earth Metals more likely to GAIN the 6 needed electrons or LOSE the 2 electron that it has?
Which one of the following substances would be the most soluble in cyclohexane, c6h12? nano3 ch3ch2oh c5h12 hi nh3
The solvent that is most soluble in it will be nonpolar C4H10.
What is nonpolar?In chemistry, polarity is the separation of electric charge, which causes a molecule or its chemical groups to have an electric dipole moment, with a negatively charged end and a positively charged end.
Due to a difference in electronegativity between the bound atoms, polar molecules must have one or more polar bonds. If the bond dipoles cancel each other out through symmetry, molecules with polar bonds have no molecular polarity.
Dipole-dipole intermolecular forces and hydrogen bonding are two ways that polar molecules communicate with one another. Surface tension, solubility, melting and boiling points, as well as other physical characteristics, are all governed by polarity.
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when the body is able to keep balance. some examples include getting more oxygen when needed and getting a fever to kill of viruses.
yin
triple beam
Homeostasis
yang
Answer: Homeostasis
Explanation: Homeostasis refers to stable equilibrium in the body. It is the condition of optimal functioning for a living organism, where no part of the body has excess stress put upon it. Some more examples of homeostasis include maintaining normal body temperature and blood sugar levels.
Answer:
Homeostasis
..・ヾ(。＞＜)シ
Is flour homogeneous or heterogeneous mixture?
Answer:
Flour is heterogeneous mixture.
Explanation:
Because you can see the different parts of the mixture,And they're normally not uniformly mixed.
If the initial concentration of so2cl2 is 0.150 m what is the concentration of so2cl2 after 220 s?
After 210 seconds, 0 e(- kt) = [SO2Cl2]0 (1 - e(- kt)) starting with 0.150M of [SO2Cl2]
[SO2]= 0.150M (1 - e) (1.48 104s 1 000 240 s)
What is concentration of a solution?
The quantity of a solute in a solvent is what we refer to in chemistry as the concentration of a solution. We refer to a solution as being concentrated when there is more solute present. Conversely, we refer to a solution as being diluted when it contains more solvent.
Utilize the integrated first order rate law, which provides the reactant sulfuryl chloride concentration as a function of time t:
([SO2Cl2]0 is the initial concentration, and k is the rate constant.) ln[SO2Cl2] = ln[SO2Cl2]0 - kt. [SO2Cl2] = e[ln[SO2Cl2]0 - kt] = e[ln[SO2Cl2]0] e(- kt) = [SO2Cl2]0 e(- kt)
The chemical equation SO2Cl2 SO2 + Cl2 describes how SO2Cl2 breaks down.
As a result, one mole of sulphur dioxide is produced for every mole of sulfuryl chloride that was lost. The relationship between these chemicals' concentration variations is as follows:
-[SO2Cl2] = [SO2] -
[SO₂Cl₂]
[SO2Cl2] - [SO2] = [SO2] - [SO2]0.
If there wasn't any sulphur dioxide at first, the concentration is as follows:
"SO2" = "SO2Cl2"
[SO2Cl2] = 0 - [SO2Cl2]
₀ - [SO₂Cl₂]
After 210 seconds, 0 e(- kt) = [SO2Cl2]0 (1 - e(- kt)) starting with 0.150M of [SO2Cl2]
[SO2]= 0.150M (1 - e) (1.48 104s 1 000 240 s)
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The number of calories needed to raise the temperature of 32 g of water from 12 °c to 54 °c is.
1349.13 calories are required in order to raise the temperature of 32g of water from 12°C to 54°C.
what is specific heat capacity?
"The amount of heat required to change the temperature of a unit mass of the substance by one degree" is the definition of specific heat capacity for any substance. This is expressed as: Specific heat capacity is a sort of thermal inertia since it shows how resistant a substance is to changes in temperature.
Water has a specific heat capacity of about 4.2 J/g°C. As a result, to increase 1 gramme of water by 1 degree Celsius, 4.2 joules of energy are required.
By formula,
Q = mcΔT = 32*4.2*42 = 5644.8 J
One calorie= 4.184 joules
thus, Q = 5644.8/4.184 calorie = 1349.13 calories.
Thus 1349.13 calories are required in order to raise the temperature of 32g of water from 12°C to 54°C.
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When comparing 2 hydrocarbons, why would the larger, higher molecular weight molecule have a higher melting point?
When comparing two hydrocarbons, the larger, higher molecular weight molecule would have a higher melting point due to greater amounts of dispersion forces.
What are hydrocarbons?Hydrocarbons are organic compounds made up of only carbon and hydrogen. They are non-polar molecules; therefore, they do not have partial charges or hydrogen bonds. The only form of intermolecular attraction between them are dispersion forces.
What are dispersion forces?Dispersion forces are the weakest type of intermolecular forces. They exist in non-polar molecules and gases like neon, hydrogen gas and oxygen gas. It is formed by the attraction between electrons and the nucleus.
Hydrocarbons with higher molecular weights have more electrons surface area than hydrocarbons with lower molecular weights. This causes the dispersion forces between the molecules to increase, thereby causing an increase in boiling point.
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What is the mass of an object that requires a force of 25 N to accelerate at 5 m/s/s?
An object with a mass of 5 kg requires a force of 25 N to accelerate at 5 m/s/s.
Force is described as the amount of energy need to move an object, either push or pull. For an object of constant mass, force is equal to the product when you multiply mass and its acceleration.
F = ma
where F = force (N or kg m/s^2)
m = mass (kg)
a = acceleration (m/s^2)
If an object requires a force of 25 N (= 25 kg m/s^2) to accelerate at 5 m/s/s, the using the formula F = ma, solve for its mass.
F = ma
25 N = 5 m/s/s (m)
25 kg m/s^2 = 5 m/s/s (m)
25 = 5m
m = 5 kg
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What is the concentration of [h ] in molars, millimolars, and micromolars for a solution of ph 5?
concentration of [h +] in molars millimolars, and micromolars for a solution of ph 5
molar concentration of [H +] = 10^(-5)M
concentration of [H +] in millimolar = 10^(-8)milliM
concentration of [H +] in micromolar = 10^(-11)microM
What is molars, millimolar and micromolar?
The term "molar" describes the moles per litre of a solution, which is the unit of concentration molarity. The phrase is most frequently used in chemistry to refer to a solute's molar concentration in a solution. Molar concentration is measured in mol/L or M.
A millimolar is a unit used to quantify molar concentration. It is a multiple of unit molar generated from SI that is frequently stated as 10 -3 molar.
A measuring unit for molar concentration is called a micromolar. It is a multiple of unit molar generated from SI that is frequently stated as 10 -6 molar.
pH = -log 10 [H +]
Thus, molar concentration of [H +] = 10^(-5)M
concentration of [H +] in millimolar = 10^(-8)milliM
concentration of [H +] in micromolar = 10^(-11)microM
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What mass of oxygen reacts with 9.2g Sodium? 4 Na + O₂ → 2 Na₂O
Answer:
About 3.201g O2
Explanation:
Solve the given differential equation by using an appropriate substitution. the de is of the form dy dx = f(ax by c), which is given in (5) of section 2.5. dy dx = (x y 3)2
Solution for the differential equation xdx + (y - 2x)dy = 0 is x/(y(x) - 1) + log((y(x) - x)/x) c1 - log(x)
What is differential equation?A differential equation in mathematics is an equation that connects the derivatives of one or more unknown functions. Applications often involve functions that reflect physical quantities, derivatives that depict the rates at which those values change, and a differential equation that establishes a connection between the three.
One or more terms as well as the derivatives of the dependent variable in respect to the independent variable make up a differential equation (i.e., independent variable) dydx. = f (x) The independent variable in this case is "x," while the dependent variable is "y." For instance, dydx.
A function y=f(x) that satisfies the differential equation when f and its derivatives are replaced into the equation is a solution to a differential equation.
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How many positional isomers of nonene are there? (consider only linear compounds, not branched isomers.)
a. 2
b. 3
c. 4
d. 5
e. 6
Option c is correct. If we only look at linear compounds and overlook branched isomers, nonene has 4 positional isomers.
Nonene is an with the molecular formula C₉H₁₈. Many structural isomers are possible, depending on the location of the C=C double bond and the branching of the other parts of the molecule. In general, nonene has 35 positional isomers if we also consider branched isomers but the demand of the question is only regarding linear compounds, so that's why the answer is four.
The most essential nonenes are propene trimers such as tripropylene. Generally, the mixture of branched nonenes is used in the alkylation of phenol to produce nonylphenol, a precursor to detergents.
What exactly are positional isomers?
Positional isomers are constitutional isomers that share the same carbon skeleton and functional group. They differ in the location of the functional groups on the carbon chain.
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Checkout the attached image here :
The bonding of water molecules to each other with ____________ bonds is called hydrogen bonding.
The bonding of water molecules to each other with hydrogen bonds is called hydrogen bonding.
In chemistry, hydrogen bonding is crucial as it holds water molecules together tightly.
Individual water molecules are made up of oxygen and hydrogen atoms which are linked together through covalent bonds.
While adjacent molecules are attached to each other through electrostatic attractions called hydrogen bonding.
Moreover, a water molecule is a dipole substance as uneven sharing of electrons creates two poles on it. One is on the hydrogen atom which is positively charged and the other is on the oxygen atom which is negatively charged. Overall it's a neutral compound.
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Calculate the molality of each of the following aqueous solutions. (a) 4.10 m kcl solution (density of solution = 1.09 g/ml) m (b) 41.7 percent by mass nabr solution.
(a) The molality of KCl solution is 5.23 m.
(b) The molality of NaBr solution is 6.95 m.
(a) c = 4.10 M; concentration of the solution
d = 1.09 g/ml; density of KCl solution
M(KCl) = 74.55 g/mol; molar mass of the solute
b = 1000×c /1000×d - c×M(KCl)
b = 1000 × 4.1 M / 1000 × 1.9 - 4.1 × 74.55
b = 5.23 mol/kg; molality of KCl solution
(b) ω(NaBr) = 0.417; percent by mass
m = 1.0 kg; mass of the solution
m(NaBr) = 417 g; mass of the solute
n(NaBr) = 417 g ÷ 102.9 g/mol
n(NaBr) = 4.05 mol; amount of the solute
m(H₂O) = 0.583 kg; mass of water
b = n(NaBr) ÷ m(H₂O)
b = 4.05 mol ÷ 0.583 kg
b = 6.95 mol/kg; molality of NaBr solution
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What mass (in g) of potassium chlorate is required to supply the proper amount of oxygen needed to burn 123.7 g of methane?
So amount of KClO3 required = 123.7*5/3 gms = 206.166 gms.
What amount of KClO3 will be used in the experiment? How long should it be heated?shows how to set the KClO3 crucible on a clay triangle with the cover slightly ajar. Heat the crucible containing the powders gently for about 8 minutes, then vigorously for 10 minutes. Potassium chlorate (KClO3) is a powerful oxidising agent with numerous applications. It's in explosives, fireworks, safety matches, and disinfectants, among other things. You may have used it to generate oxygen in the lab as a high school or college chemistry student. While it is not the most efficient chemical reaction, making potassium chlorate is as simple as boiling bleach, cooling it, and mixing it with a saturated solution of salt substitute in water. Because potassium from the salt substitute displaces sodium from the sodium chlorate formed by boiling the bleach, the synthesis works.
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Answer question 7. Circle the largest atom or ion in each grouping (I will give brainliest)
S, S^2-, Cl
Al, Al^3+, Mg
Sb, Se, Se^2+
Ca, K^1-, Ca^2+
Be^2+, Be, Na
According to the atomic radius, the largest atom or ion in each grouping are – [tex]S^2^-[/tex], [tex]Mg[/tex] , [tex]Sb[/tex] , [tex]Ca[/tex] , [tex]Na[/tex] .
A measure of the size of an atom is the atomic radius of a chemical element, which is normally the average distance between the core of the nucleus and the outermost isolated electron. There are several non-equivalent descriptions of atomic radius since the border is not a clearly defined physical object.
Since the net nuclear charge steadily rises as a result of higher electron attraction to the nucleus, the radius of atoms decreases across a period. However, as the number of shells in each atom grows along the group, the atomic radius increases.
Neutral atoms typically become larger down a group and smaller across a period. The radius of a neutral atom increases or decreases as it acquires or releases an electron, becoming an anion or cation, respectively.
In the given groupings, the size of the atoms and ions according to the atomic radius is as follows:
[tex]S^2^- > S > Cl[/tex]
[tex]Mg > Al > Al^3^+[/tex]
[tex]Sb > Se^2^- > Se[/tex]
[tex]Ca > K^+ > Ca^2^+[/tex]
[tex]Na > Be > Be^2^+[/tex]
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A buffer is prepared by mixing 37.2 ml of 0.209 m naoh with 125.7 ml of 0.231 m acetic acid. what is the ph of this buffer? (the pka for acetic acid is 4.75.)
Calculate the moles in each reactant
Acetic Acid (.231 mol/L)(0.125L)= 2.887 x 10^-2 mol AA
NAOH (.209mol/L)(.037L)= 7.733 x 10^-3 mol NaOH
As you can see, we have more AA and less NaOH, so NaOH is the limiting reactant.
NaOH + CH3COOH -> NaCH3COOH + H2O
start: 4.5 mmol, 8.75mmol, 0, n/a
change: -4.5 mmol, -4.5mmol, 4.5mmol, n/a
after rxn: 0, 4.25 mmol, 4.5mmol, n/a
Now your HH equation
pKa + log(conjugate base/acid) = 4.75 + log(4.5x10^-3 / 4.25x10^-3) =
pH = 4.76
What is Henderson-Hasselbalch equation?The Henderson-Hasselbalch equation in chemistry and biology connects the pH of a weak acid solution to its acid dissociation constant, Ka, and the ratio of the concentrations of the acid and its conjugate base in equilibrium.
When both the pH of the solution and the ratio of ionized to unionized forms are known, the Henderson Hasselbalch equation can be used to calculate the pKa.
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