Answer:
[tex]\boxed {\boxed {\sf 8.22 \ \textdegree C}}[/tex]
Explanation:
The question asks us to calculate the temperature of the gas at the higher volume. Since the pressure is constant, we are only concerned about volume and temperature. We will use Charles's Law. This states that the volume of a gas and the temperature of the gas have a directly proportionate relationship. The formula is:
[tex]\frac {V_1}{T_1}= \frac{V_2}{T_2}[/tex]
The gas starts at a volume of 4.17 liters and a temperature of 7.62 degrees Celsius.
[tex]\frac {4.17 \ L}{7.62 \textdegree C} = \frac{V_2}{T_2}[/tex]
The gas is expanded to a new volume of 4.50 liters, but the temperature is unknown.
[tex]\frac {4.17 \ L}{7.62 \textdegree C} = \frac{4.50 \ L}{T_2}[/tex]
We want to solve for the temperature at a higher volume. We must isolate the variable T₂. Cross multiply. Multiply the first numerator and second denominator, then the first denominator and second numerator.
[tex]4.17 \ L * T_2 = 4.50 \ L * 7.62 \textdegree C[/tex]
The variable is being multiplied by 4.17 liters. The inverse of multiplication is division. Divide both sides by 4.17 L.
[tex]\frac {4.17 \ L * T_2 }{4.17 \ L}= \frac{4.50 \ L * 7.62 \textdegree C}{4.17 \ L}[/tex]
[tex]T_2=\frac{4.50 \ L * 7.62 \textdegree C}{4.17 \ L}[/tex]
The units of liters (L) cancel.
[tex]T_2=\frac{4.50 * 7.62 \textdegree C}{4.17 }[/tex]
[tex]T_2=\frac{34.29}{4.17 } \textdegree C[/tex]
[tex]T_2=8.22302158273 \textdegree C[/tex]
The original measurements of liters and temperature have 3 significant figures, so our answer must have the same. For the number we calculated, that is the hundredth place.
The 3 to the right in the thousandth place tells us to leave the 2 in the hundredth place.
[tex]T_2 \approx 8.22 \ \textdegree C[/tex]
The temperature of the gas at the higher volume is approximately 8.22 degrees Celsius.
The following list of properties is most descriptive of a(n) ______________. Low melting point, non-conductor of electric current. Group of answer choices
Answer:
This question is incomplete
Explanation:
This question is incomplete but the completed question is below;
"The following list of properties is most descriptive of a(n) ______
1. High melting point, conductor of electricity when dissolved in water
2. Low melting point, non-conductor of electric current
3. Malleable, ductile, insoluble in water.
The choices for all 3 are: a) metallic solid b) molecular solid c) ionic solid d) all of these e) none of these f) more than one of these"
1. Ionic solid: Ionic solids are solids that have ionic/electrovalent bonds holding it's constituent molecules together. These bonds are strong bonds that involve the transfer of electrons from one constituent atom (the metal) to another constituent atom (the nonmetal). This strong bond causes the solid to have a high melting and boiling point. Also, when dissolved in water, the constituent atoms (involved in the electron transfer) dissociate to form ions (become charged) and thus easily carry electric charges (i.e conduct electricity).
Examples are Sodium Chloride and Potassium Iodide
2. Molecular solids: These are solids whose constituent molecules are held together by a weak bond/force known as Van der Waal forces. This forces are easily broken down when subjected to heat and thus the molecular solids have a low melting point. Also, these solids do not have carriers of heat or electric charges in them and are thus non-conductors of electric current.
Examples are Ice (frozen water) and sucrose
3. Metallic solids: These of solids made from constituent metal atoms only. The nuclei of these constituent metal atoms have the ability to move past one another without disrupting there metallic bonding; it is for this reason they are malleable and ductile. There constituent atoms however do not dissociate in water and are thus insoluble in water.
Examples are aluminium and copper crystal.
Write a balanced half-reaction for the reduction of liquid water to gaseous hydrogen in basic aqueous solution. Be sure to add physical state symbols where appropriate.
Answer:
2 H₂O(l) + 2 e⁻ ⇒ H₂(g) + 2 OH⁻(aq)
Explanation:
Let's consider the unbalanced half-reaction for the reduction of liquid water to gaseous hydrogen in basic aqueous solution.
H₂O(l) ⇒ H₂(g)
First, we will perform the mass balance. We will balance oxygen atoms by multiplying H₂O by 2 and adding 2 OH⁻ to the right side.
2 H₂O(l) ⇒ H₂(g) + 2 OH⁻(aq)
Then, we perform the charge balance by adding 2 electrons to the left side.
2 H₂O(l) + 2 e⁻ ⇒ H₂(g) + 2 OH⁻(aq)
which molecule has 9 carbon atoms
Answer:
c9h8o2
Explanation:
The molecule which has 9 carbon atom is [tex]C_{9} H_{8} O[/tex](cinnamaldehyde).
What is molecule?More than one atoms make up a molecule. If they have more than one atom, atoms could be the same for example, an oxygen molecule contains two oxygen atoms) as well as different (for example, a hydrogen molecule contains two hydrogen atoms.
What is cinnamaldehyde?Cinnamaldehyde is a kind of organic chemical with the formula C6H5CH=CHCHO and the formula C6H5CH=CHCHO. It's mostly the trans isomer that's found in nature.
It is known that the number of carbon atom is 9 hence molecule will be cinnamaldehyde
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Select the more electronegative element in this pair.
a. Cl F
b. O P
c. N C
d. Be Li
Answer:
a. F
b. O
c. N
d. Be
Explanation:
Electronegative is a periodic table for the elements which is stated by the Pauling number. EN helps us to state the type of bond which it can be covalent or ionic.
Fluroine is the most electronegative number of the periodic table.
In option A, F (4) is more EN than Cl (3.2)
EN is decreased from right to left in the periodic table (if we see periods) and increases, from bottom to top if we look at the groups
In option B, O (3.4) is more EN than P (2.2)
In option C, N (3) is more EN than C (2.6)
In Option D, Be (1.5) is more EN than Li (1)
If a 520 mg sample of technetium-99 is used for diagnostic procedure, how much of Tc-99 remains after 30.0h? Half life of Tc-99 is 6.0 hours.
What is the molarity of a solution containing 150 g of zinc sulfate (ZnSO4) per liter?
Answer:
0.93 M
Step-by-step Explanation:
First, we have to calculate the molar mass (MM) of ZnSO₄ by using the molar mass of each chemical element:
MM(ZnSO₄) = 65.4 g/mol Zn + 32 g/mol S + (16 g/mol x 4) = 161.4 g/mol
Then, we divide the mass of ZnSO₄ into its molar mass to obtain the number of moles:
moles ZnSO₄ = mass/MM = 150 g/(161.4 g/mol)= 0.93 mol
Since the molarity of a solution expresses the number of moles of solute per liter of solution, we calculate the molarity (M) as follows:
M = moles ZnSO₄/1 L = 0.93 mol/1 L = 0.93 M
from kinatic point of view explain the change from solid to liquied based on the effect of change of tempreture.
Answer:
Temperature affects the kinetic energy in a gas the most, followed by a comparable liquid, and then a comparable solid. The higher the temperature, the higher the average kinetic energy, but the magnitude of this difference depends on the amount of motion intrinsically present within these phases.
Explanation:
Liquids have more kinetic energy than solids. When a substance increases in temperature, heat is being added, and its particles are gaining kinetic energy. Because of their close proximity to one another, liquid and solid particles experience intermolecular forces. These forces keep particles close together.
2) If a brick has a length of 13.77 cm, a width of 8.50 cm, and a height of 5.12 cm:
a) What is the volume of the brick?
b) If the brick has a mass of 895.3 g, what is its density?
Answer:
a. 599 cm³
b. 1.49 g/cm³
Explanation:
A. VolumeVolume is the amount of space an object occupies. Since this is a brick, the object is a rectangular prism. The formula for the volume of a rectangular prism is the product of length, width, and height.
[tex]V= l *w*h[/tex]
The brick's length (l) is 13.77 centimeters, the width (w) is 8.50 centimeters, and the height (h) is 5.12 centimeters. Substitute these values into the formula.
[tex]V= 13.77 \ cm * 8.50 \ cm * 5.12 \ cm[/tex]
Multiply the numbers together.
[tex]V= 117.045 \ cm^ 2* 5.12 \ cm[/tex]
[tex]V= 599.2704 \ cm^3[/tex]
The original measurements have at least 3 significant figures, so our answer must have 3. For the number we calculated, that is the ones place. The 2 in the tenths place tells us to leave the 9 in the ones place.
[tex]V \approx 599 \ cm^3[/tex]
[tex]\bold {The \ volume \ of \ the \ brick \ is \ approximately \ 599 \ cubic \ centimeters}}[/tex]
2. DensityDensity is the amount of matter in a specified space. The formula for density is mass over volume.
[tex]d= \frac{m}{v}[/tex]
The mass of the brick is 895.3 grams and we just found the volume to be 599.2704 cubic centimeters. Substitute the values into the formula.
[tex]d= \frac{895.3 \ g}{599 \ cm^3}[/tex]
Divide.
[tex]d= 1.494657763 \ g/cm^3[/tex]
Round to three significant figures. For the number we calculated, that is the hundredth place. The 4 in the thousandth place tells us to leave the 9 in the hundredth place.
[tex]d \approx 1.49 \ g/cm^3[/tex]
[tex]\bold {The \ density\ of \ the \ brick \ is \ approximately \ 1.49 \ grams /cubic \ centimeters}}[/tex]
Sobre ações relacionadas ao aquecimento global, assinale somente as alternativas corretas:
a) ( x) As ações humanas não influenciam no aumento da temperatura do planeta.
b) ( ) As mudanças climáticas são intensificadas pela emissão de gases das atividades humanas.
c) ( ) A queima de combustíveis fósseis e de florestas são as principais ações humanas que liberam gases que intensificam o efeito estufa.
d) ( ) O efeito estufa é um fenômeno natural.
e) ( ) Se as águas dos oceanos ficarem mais quentes, os furacões não terão tanta força.
Answer:
123456788012346778901234567890
3. At 35 C, a sample of gas has a volume of 256 ml and a pressure of 720.torr. What would the volume
be if the temperature were changed to 22 C and the pressure to 1.25 atmospheres
Answer:
The volume will be 185.83 mL.
Explanation:
Gay-Lussac's law indicates that when there is a constant volume, as the temperature increases, the pressure of the gas increases. And when the temperature is decreased, the pressure of the gas decreases. Gay-Lussac's law can be expressed mathematically as follows:
[tex]\frac{P}{T} =k[/tex]
Where P = pressure, T = temperature, k = Constant
Boyle's law says that the volume occupied by a given gaseous mass at constant temperature is inversely proportional to pressure. Boyle's law is expressed mathematically as:
P*V=k
Where P = pressure, V = volume, k = Constant
Finally, Charles's Law consists of the relationship that exists between the volume and the temperature of a certain quantity of ideal gas, which is kept at a constant pressure. For a given sum of gas at a constant pressure, as the temperature increases, the volume of the gas increases and as the temperature decreases, the volume of the gas decreases because the temperature is directly related to the energy of the movement of the gas molecules. .
In summary, Charles's law is a law that says that when the amount of gas and pressure are kept constant, the quotient that exists between the volume and the temperature will always have the same value:
[tex]\frac{V}{T} =k[/tex]
Combined law equation is the combination of three gas laws called Boyle's, Charlie's and Gay-Lusac's law:
[tex]\frac{P*V}{T} =k[/tex]
Studying two different states, an initial state 1 and a final state 2, it is satisfied:
[tex]\frac{P1*V1}{T1} =\frac{P2*V2}{T2}[/tex]
In this case:
P1= 720 torr V1= 256 mLT1= 35 C= 308 K (being 0 C= 273 K)P2= 1.25 atm= 950 torr (being 1 atm= 760 torr)V2= ?T2= 22 C= 295 KReplacing:
[tex]\frac{720 torr*256 mL}{308 K} =\frac{950 torr*V2}{295 K}[/tex]
Solving:
[tex]V2= \frac{295K}{950 torr} *\frac{720 torr*256 mL}{308 K}[/tex]
V2= 185.83 mL
The volume will be 185.83 mL.
How many atoms are in protons
Answer:
the number of protons in a atom is unique to each element
Explanation:
protons are about 99.86% as massive neutrons. The number of protons in a atom is unique to each element .For example carbon atoms have six protons in an atom is referred to as the atomic number of that element
Carbonic anhydrase is strongly inhibited by the drug acetazolamide, which is used as a diuretic (i.e., to increase the production of urine) and to lower excessively high pressure in the eye (due to accumulation of intraocular fluid) in glaucoma.
a. True
b. False
Answer:
a. True
Explanation:
There is strong inhibition of Carbon Anhydrase by Aceta-zolamide Carbonic Anhydrase. The drug acetazolamide is used as diuretic which increase the urine production in human body. It lowers pressure in eye in glaucoma.
A hydrocarbon contains only the elements____?
Explanation:
elements are carbons and hydrogen
Answer:
Carbon and Hydrogen.
Explanation:
It’s in the name Hydro (H) Carbon (C)
When heated, carboxylic salts in which there is a good leaving group on the carbon beta to the carbonyl group undergo decarboxylation/elimination to give an alkene. Draw the structures of the products expected when this compound is heated.
Answer:
i dont know mate
Explanation:
What type of intermolecular force exist between H2O and Br2
Answer:
welcome to mobile legends
Explanation:
ml ka muna maya kana mag module
A 2.584 g sample of a compound containing only carbon, hydrogen, and oxygen is burned in an excess of dioxygen, producing 5.874 g CO2 and 2.404 g H2O. What mass of oxygen is contained in the original sample?a. 0.7119 g.b. 0.8463 g.c. 0.29168 g.d. 0.1793 g.e. 0.6230 g.
Answer:
a. 0.7119 g
Explanation:
To solve this question we need to know that all carbon of the compound will react producing CO2 and all Hydrogen producing H2O.
Thus, we can find the mass of C and the mass of H and by difference regard to the 2.584g of the compound we can find the mass of oxygen as follows:
Moles CO2 = Moles C -Molar mass: 44.01g/mol-
5.874g CO2 * (1mol/44.01g) = 0.1335 moles CO2 = 0.1335 moles C
Mass C -Molar mass: 12.01g/mol-:
0.1335 moles C * (12.01g /mol) = 1.6030g C
Moles H2O -Molar mass: 18.01g/mol-
2.404gH2O * (1mol / 18.01g) = 0.1335 moles H2O * (2mol H / 1mol H2O) = 0.267 moles H
Mass H -Molar mass: 1g/mol-
0.267 moles H * (1g/mol) = 0.2670g H
Mass Oxygen =
Mass O = 2.584g compound - 1.6030g C - 0.2670g H
Mass O = 0.714g O ≈
a. 0.7119 gnet ionic equation for 2AgF(aq) + k2S = Ag2S (s) + 2KF(aq)
Answer:
The net ionic equation shows the actual reaction more clearly and closer to reality because it writes soluble ionic compounds as the ions and then cancel the spectator ions not involved in the chemical reaction . The net ionic equation results shows the actual chemical reaction taking place.
The net ionic equation for for 2AgF(aq) + k₂S = Ag₂S (s) + 2KF(aq) will be; 2 Ag⁺(aq) + S²⁻(aq) → Ag₂S(s).
To write the net ionic equation for the reaction, we first need to write the balanced molecular equation and then convert it into the ionic equation before finally identifying the net ionic equation.
Write the balanced molecular equation:
2 AgF(aq) + K₂S(aq) → Ag₂S(s) + 2 KF(aq)
In this reaction, silver fluoride (AgF) reacts with potassium sulfide (K₂S) to produce silver sulfide (Ag₂S) and potassium fluoride (KF).
Write the complete ionic equation:
In the complete ionic equation, we separate all the aqueous species (dissociated ions) into their individual ions. Only the solid (s) and gas (g) compounds remain unchanged.
2 Ag⁺(aq) + 2 F⁻(aq) + 2 K⁺(aq) + S²⁻(aq) → Ag₂S(s) + 2 K⁺(aq) + 2 F⁻(aq)
Identify the spectator ions and then write the net ionic equation:
The spectator ions are the ions that do not participate in the actual chemical reaction and remain the same on both sides of the equation. In this reaction, the potassium ions (K⁺) and fluoride ions (F⁻) are spectator ions because they appear on both sides of the equation unchanged.
Net ionic equation:
2 Ag⁺(aq) + S²⁻(aq) → Ag₂S(s)
The net ionic equation shows only the species that actively participate in the chemical reaction. In this case, the silver ions (Ag⁺) and sulfide ions (S²⁻) are the ones involved in forming the silver sulfide (Ag₂S) precipitate.
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--The given question is incomplete, the complete question is
"Write the net ionic equation for this reaction. 2AgF(aq) + k₂S = Ag₂S (s) + 2KF(aq)."--
Which technique is best suited to each application?
a. In the second week of a four week biochemistry experiement, you have 50 fractions collected from a gel filtration column to determine which fractions contain lactate dehydrogenase. You are given only 400 uL of 0.100 mg/mL lactate dehydrogenase to prepare your calibration curve. 96-well microplate
b. Your environmental lab has 2000 samples to be analyzed for trace ammonia by next week. discrete analyzer.
c. Twenty water samples must be analyzed for Cl-, NH3, PO3-, and So during each work shift. flow injection analysis colorimeter.
d. Your professor heard you will be hiking the Appalachian Trail next summer. She asks you to collect 100-mL water samples from the ten streams with the highest concentration of phosphate.
Answer:
a. discrete analyzer
b. 96 well microplate
c. flow injection analysis
d. colorimeter
Explanation:
96 well microplates are instruments designed for sample collection and throughput screening. If an environment lab has collected 2000 samples then 96 well microplate is best suited application. Discrete analyzer is automated chemical analyzer which performs test on samples kept in discrete cells. Flow injection analysis is approach used for chemical analysis. It injects a plug of sample into a flowing carrier stream. Colorimeter is a device which measures absorbance of wavelength of light by a specific solution.
Ethylene glycol (C2H6O2) is mixed with water to make auto engine coolants. How many grams of C2H6O2 are in 5.00 L of a 6.00 M aqueous solution
Answer:
1860g.
Explanation:
It is known that the molar mass of C2H6O2 is 62.08 g/mol.,
Now to solve for the number of moles of solute, one must multiply both
sides by the volume:
moles of solute = (6.00 M)(5.00 L) = 30.0 mol
Notice since the definition of molarity is mol/L, the
product M × L gives mol, a unit of amount.
Use the molar mass of C3H8O3, one can convert mol to g:
Mass m =30 mol × 62.08 g/mol
m = 1860g.
Hence, there are 1,860 g of C2H6O2 in the specified amount of
engine coolant.
Leaming Task 1:
Distinguish the process as spontaneous or non-spontaneous process. Write S it spontaneous and NSi non-spontaneous
on the bionk.
1. Melling ofice
2 Ruisting of ton
3. Marble going down the spiral.
4. Going up the
& Keeping the food fresh from spolage
Solution :
Spontaneous Process
A spontaneous process is defined as the process that occurs without the help of any external aid or inputs. A spontaneous process is a natural process which occurs naturally in the environment.
Non Spontaneous process
A non spontaneous process is a process which does not occur naturally. Some inputs are provided for the process to occur. Energy from external source is applied into the process to start the process.
The following processes are :
1. Melling of ice ---- Spontaneous
2 Rusting of iron --- Spontaneous
3. Marble going down the spiral. --- spontaneous
4. Going up the hill ---- Non spontaneous
5. Keeping the food fresh from spoilage --- Non spontaneous
0.28 M Ca(NO3)2
Express your answer using two significant figures.
Answer:
Mass=Moles × RFM
Mass= 0.28M× 164
Mass= 45.92 grammes
A gas occupies a volume of 202 ml at a pressure of 505 torr. To what pressure must the gas be subject in order to change the volume to 65.0 ml
Answer:
1569 torr
Explanation:
Assuming ideal behaviour and constant temperature, we can solve this problem by using Boyle's law, which states:
V₁P₁ = V₂P₂Where in this case:
V₁ = 202 mLP₁ = 505 torrV₂ = 65.0 mLP₂ = ?We input the data given by the problem:
202 mL * 505 torr = 65.0 mL * P₂And solve for P₂:
P₂ = 1569 torrWhat is the molecular geometry of CIO3F as predicted by the VSEPR model?
Multiple Choice
trigonal pyramidal
square planar
square pyramidal
tetrahedral
octahedral
Explanation:
since there are no lone pairs on the central atom, the shape will be tetrahedral
give one use of zinc
Which acid or base (along with its corresponding salt) should be used to generate a buffer solution with pH around 3.5
Answer:
Formic acid
Sodium formiate
Explanation:
To determine acid or base that can generate a buffer solution with pH around 3.5, we have to think in the acid whose pKa = pH.
Although we have to also think in buffer capacity, a measure which can cause a change of 1 pH unit in 1 L of solution.
Buffer capacity does not only depend on the concentration of its components but also of the relationship between that concentrations.
When pH = pKa, buffer capacity is maximum which means that the concentration of conjugated species is the same and the ability to oppose pH changes is maximum.
One example with pH = pKa or nearly if:
COOH⁻ + Na⁺ → NaCOOH
HCOOH + H₂O → COOH⁻ + H₃O⁺ Ka: 1.8×10⁻⁴
pKa = 3.74
Plastic is a polymer
-True
-False
TRUE
Explanation:
*not sure about this answer
What is the direct function of the energy released from the nuclear chain reaction in a nuclear power plant? turning the blades of the turbine heating water to produce steam powering the condenser carrying electricity from the plant to consumers
Answer:
the energy released is to make steam to create electricity. yes you are right i just didnt feel like being super technical
In a nuclear reaction, the direct function of the energy released from the nuclear chain reaction in a nuclear power plant is turning the blades of the turbine heating water to produce steam .
What are nuclear reactions?There are two types of nuclear reactions which are nuclear fusion and nuclear fission .They involve the combination and disintegration of the element's nucleus respectively.
In nuclear fission, the nucleus of the atom is bombarded with electrons of low energy which splits the nucleus in to two parts .Large amount of energy is released in the process.It is used in nuclear power reactors as it produces large amount of energy.
In nuclear fusion,on the other hand, is a reaction which occurs when two or more atoms combine to form a heavy nucleus.Large amount of energy is released in the process which is greater than that of the energy which is released in nuclear fission process.
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Assuming tea leaves contain 5.0% caffeine by weight what is the maximum weight of caffeine you could isolate from 10.g of tea leaves? Show your work.
Answer:
0.50 g Caffeine
Explanation:
Step 1: Given data
Concentration of caffeine by weight in tea leaves: 5.0%
Mass of tea leaves: 10. g
Step 2: Calculate the maximum weight of caffeine that can be isolated
The concentration of caffeine by weight in tea leaves is 5.0%, that is, there are 5.0 g of caffeine per 100 g of tea leaves. The maximum weight of caffeine in 10. g of tea leaves is:
10. g Tea leaves × 5.0 g Caffeine/100 g Tea leaves = 0.50 g Caffeine
In aqueous solution the Ni2" ion forms a complex with four ammonia molecules. Write the formation constant expression for the equilibrium between the hydrated metal ion and the aqueous complex. Under that, write the balanced chemical equation for the first step in the formation of the complex K,=________.
Answer:
The correct equation is "[tex]\frac{[Ni(H_2O)_3 (NH_3)]^{2+}}{[Ni(H_2O)_4]^{2+} [NH_3]}[/tex]".
Explanation:
According to the question,
Throughout an aqueous solution, [tex]Ni^{2+}[/tex] exist as [tex][Ni(H_2O)_4]^{2+}[/tex]
So,
⇒ [tex][Ni(H_2O)_4]^{2+} + 4NH_3 \rightleftharpoons [Ni(NH_3)_4]^{2+} + H_2O[/tex]
⇒ [tex]K_f = \frac{[Ni(NH_3)_4]^{2+}}{[Ni(H_2O)_4^{2+}] [NH_3]^4}[/tex]
Here, we have excluded [tex][H_2O][/tex] as concentration of water will be const.
Now,
This formation of [tex][Ni(NH_3)_4]^{2+}[/tex] proceeds via several steps,
Step 1:
⇒ [tex][Ni(H_2O)_4]^{2+}+NH_3 \rightleftharpoons [Ni(H_2O)_3 (NH_3)]^{2+} + H_2O[/tex]
⇒ [tex]K_1 = \frac{[Ni(H_2O)_3 (NH_3)]^{2+}}{[Ni(H_2O)_4]^{2+} [NH_3]}[/tex]
You need to produce a buffer solution that has a pH of 5.50. You already have a solution that contains 10 mmol (millimoles) of acetic acid. How many millimoles of acetate (the conjugate base of acetic acid) will you need to add to this solution?
Answer:
56.9 mmoles of acetate are required in this buffer
Explanation:
To solve this, we can think in the Henderson Hasselbach equation:
pH = pKa + log ([CH₃COO⁻] / [CH₃COOH])
To make the buffer we know:
CH₃COOH + H₂O ⇄ CH₃COO⁻ + H₃O⁺ Ka
We know that Ka from acetic acid is: 1.8×10⁻⁵
pKa = - log Ka
pKa = 4.74
We replace data:
5.5 = 4.74 + log ([acetate] / 10 mmol)
5.5 - 4.74 = log ([acetate] / 10 mmol)
0.755 = log ([acetate] / 10 mmol)
10⁰'⁷⁵⁵ = ([acetate] / 10 mmol)
5.69 = ([acetate] / 10 mmol)
5.69 . 10 = [acetate] → 56.9 mmoles
