1.39 mol HF is added to enough 0.156-M NaF solution to give a final volume of 1.7 L. What is the pH of the resulting solution given that the Ka of HF is 3.5x10-4 under these conditions?
a. 2.74
b. 2.65
c. 1.41
d. 0.09
e. 2.82
Answers
To calculate the pH of the resulting solution, we can use the concept of the Henderson-Hasselbalch equation, which relates the pH of a weak acid solution to the concentration of the acid and its conjugate base.
Given:
Initial concentration of HF (weak acid) = 1.39 mol
Concentration of NaF (conjugate base) = 0.156 M
Final volume of solution = 1.7 L
Ka of HF = 3.5x10^-4
First, we need to calculate the concentration of HF and F- (conjugate base) in the final solution after the reaction occurs:
HF concentration = Initial concentration - moles of HF reacted with NaF
HF concentration = 1.39 mol - (moles of NaF formed from the reaction)
Since HF and NaF react in a 1:1 ratio, the moles of NaF formed will be equal to the moles of HF reacted. So, moles of NaF formed = 1.39 mol.
Concentration of F- (conjugate base) in the final solution = Concentration of NaF formed = 1.39 M
Now, we can use the Henderson-Hasselbalch equation:
pH = pKa + log([conjugate base]/[weak acid])
pKa is the negative logarithm of Ka, so pKa = -log(Ka) = -log(3.5x10^-4)
Substituting the values:
pH = -log(3.5x10^-4) + log(1.39/0.156)
Using logarithm properties, we can simplify the equation:
pH = -log(3.5x10^-4) + log(8.91)
pH = -(-3.4559) + 0.9500
pH ≈ 2.74
So, the correct answer is option (a) 2.74.
To know more about conjugate click here:
brainly.com/question/29870475
#SPJ11
Related Questions
f the two electrodes were completely inert and did not participate in the reaction, what potential would have to be exerted on the cell to produce molten al at 1000 oc? the oxygen produced is at 1 bar.
Answers
Anode in a bath of molten cryolite heated to between 950 and 1000 °C is part of an electrolytic reduction cell for the manufacture of metal.
How much voltage does electrolysis happen at?The Faraday constant F represents the charge of a mole of electrons (96485 C/mol), and since each mole of water requires two moles of electrons, the minimum voltage required for electrolysis is roughly 1.23 V. This voltage decreases when electrolysis is performed at a high temperature.
Does raising voltage increase electrolysis?Therefore, during electrolysis, the rate of the reaction increases as voltage is raised. The nature and material of the electrode, the presence of oxidizing and reducing chemicals in the electrolyte, and electrode potential are the parameters that affect the electrolysis process.
To know more about molten cryolite visit:-
https://brainly.com/question/23952256
#SPJ4
Can you help me solve these problems step by step. 35 points.
Answers
Answer:
Explanation:
Multiply no of moles with the molar mass of the compounds
a. 3.4*16= 54.4g
b. 0.2*40= 8g
c. 2.1*111= 233g
d. 9.2*331= 3045.2g
e. 1.2*310= 372g
potassium iodide compound is represented by which formula?
A)
Ky!
B)
Kyl2
КІ
D)
KI2
Answers
Answer:
KI is the formula for potassium iodide
Explanation:
hope this helpssss :D
don't forget to be stunning!!!
A radioactive isotope has a half-life of 20 years. You start with 80 grams of the isotope. How long does it take until it decays to 2.5 grams
Answers
It will take approximately 86.44 years for the radioactive isotope to decay from 80 grams to 2.5 grams, assuming the decay follows a simple exponential decay model.
The decay of a radioactive isotope can be modeled using the formula:
N = N0 * (1/2\()^(t/t1/2)\)
where N is the amount of the isotope at a given time t, N0 is the initial amount, t1/2 is the half-life of the isotope, and t is the elapsed time.
In this case, we are given N0 = 80 grams, t1/2 = 20 years, and we want to find the value of t when N = 2.5 grams. Therefore, we can set up the following equation:
2.5 = 80 * (1/2)\(^(t/20)\)
Dividing both sides by 80, we get:
(1/2\()^(t/20)\) = 2.5/80
Taking the logarithm of both sides with base 1/2, we get:
t/20 = log(2.5/80) / log(1/2)
Simplifying this expression, we get:
t/20 = 4.3219
Multiplying both sides by 20, we get:
t = 86.44 years
Therefore, it will take approximately 86.44 years for the radioactive isotope to decay from 80 grams to 2.5 grams, assuming the decay follows a simple exponential decay model.
Learn more about radioactive isotope
https://brainly.com/question/1907960
#SPJ4
1. How many elements are in the following equation, FeCrO4 ?
1
2
3
4
O
Answers
3 is the number of element that are in the following equation, FeCrO\(_4\) . Therefore, the correct option is option C.
An element comprises a pure substance made up of only one kind of atom, each of whose nuclei contains the same amount of protons. The debate over the theoretical character of the word "element" offers a very singular chance to look at how chemists and chemical philosophers currently interact. The English scientist Robert Boyle was the one who first proposed the chemical element.
Number of Fe element = 1
Number of Cr element = 1
Number of O element = 1
Total element = 3
Therefore, the correct option is option C.
To know more about element, here:
https://brainly.com/question/31950312
#SPJ6
You're working in a lab at Clemson university, and your professor wants to make one of the existing polymers stronger and more rigid. He says, "Pop quiz, lab rats. What do we need to do to this polymer to strengthen it?" Explain two simple ways synthetic polymers can be made stronger and more rigid?
Answers
Cross-linking polymers not only increases the tensile strength of the polymer, but it also changes the polymer's elastic properties.
What are polymers ?The term polymer is defined as any of a class of natural or synthetic material composed of very large molecules, called macromolecules, that are multiples of simpler chemical units called monomers.
Adding cross-links between polymer chains initially makes the polymer more elastic. The introduction of short chains of sulfur atoms that link the polymer chains in natural rubber, for example, results in the vulcanization of rubber. The polymer becomes more rigid as the number of cross-links increases.
Thus, Cross-linking polymers not only increases the tensile strength of the polymer, but it also changes the polymer's elastic properties.
To learn more about the polymer, follow the link;
https://brainly.com/question/17354715
#SPJ1
6. If the pressure of a gas is 1.01 atm and the temperature is 25°C, then if the pressure is increased to 1.10, what is the new temperature?
Answers
Answer:
324.554 K
Explanation:
Which can be converted back to °C by subtracting 273
Once again thus answer can be found using the gas law P1/T1 =P2/T2
Remember to convert to Kelvin before doing the calculations by adding 273
________ is dissolved in water to make the solution sold commercially as rubbing alcohol.
Answers
Answer:
Isopropyl alcohol or Propan-2-ol
Explanation:
Hope it helps!
how does an airplane’s kinetic energy and potential energy change as it takes off and lands? How does this energy change relate to the law of conservation of energy?
Answers
Answer: As the airplane goes higher, the mechanical energy is changed into gravitational potential energy. While flying, some energy is lost through drag to thermal (heat) energy and sound energy. Some is also lost as the plane makes the air around it move. ... As speed and height decrease, kinetic and potential energy decrease.
Explanation:
Hope this help
What happens when a wave hits an object?
A) the wave is reflected
B) the wave continues on
C) the wave is interfered with
D) the wave stops
Answers
Answer:
C) the wave is interfered with
How does the concentration of soudium thiosulfate affect the rate of reaction with dilute hydrochloric acid?
Your plan should give valid results.
Answers
Answer:
As the concentration of Sodium Thiosulphate increases the length of time for cross to disappear decreases. This is because the increase of concentration of Sodium Thiosulphate will increase the rate of reaction between Hydrochloric acid and sodium Thiosulphate particles.
Explanation:
Logic...
The final electron acceptor in aerobic respiration is....... NAD water oxygen pyruvate O hydrogen . Answer al Question 16 Which of the following processes generate carbon dioxide? Hint There are more than one. Glycolysis Oxidative Phosphorylation The Link Reaction (pyruvate oxidation) The Citric Arid Cycle Lactic Acid Fermentation Alcoholic Fermentation
Answers
The final electron acceptor in aerobic respiration is oxygen (O2).The electron transport chain (ETC) in cellular respiration relies on a final electron acceptor to help oxygen get reduced into water. This is why oxygen is considered the final electron acceptor in cellular respiration.
During cellular respiration, glucose is broken down into pyruvate. Pyruvate is then transformed into acetyl CoA and enters the citric acid cycle, where it is oxidized and generates ATP, NADH, and FADH2. The final stage of aerobic respiration involves the electron transport chain, in which electrons from NADH and FADH2 are passed through a series of proteins and coenzymes in the inner mitochondrial membrane, ultimately reducing oxygen to form water.
This process is known as oxidative phosphorylation.In conclusion, the final electron acceptor in aerobic respiration is oxygen (O2), and carbon dioxide is generated in the link reaction (pyruvate oxidation) and the citric acid cycle.
To know more about cellular respiration visit:-
https://brainly.com/question/32872970
#SPJ11
Select the correct layer.
In which layer is lithification most likely to occur?
Answers
Answer:
"Subsoil" is the correct answer.
Explanation:
The method of transforming sediments become rocky solids is considered as Lithification. The floor stratum or level below the upper floors at the base of the floor is a Subsoil.Sediments comprise materials particles like sand, pebbles, skeletons kind of bones as well as muck, that were transported and produced instead in water or perhaps wind someplace.Answer: subsoil is the second layer meaning it's
Explanation:
i researched what layer subsoil is
the electron configruration of an atom in the ground state is 2-4 the total number if occupied principal energey levels im this atom is
Answers
Answer:
2 energy levels
Explanation:
when this compound undergoes hydrolysis in acid, what product(s) are obtained? group of answer choices butanoic acid and butanol butanoic acid and ethanol butanoic acid ethanoic acid and butanol ethanol
Answers
When the given compound undergoes hydrolysis in acid, the products obtained are butanoic acid and ethanol. Hydrolysis is a reaction in which a compound is broken down by the addition of water.
In this case, the ester bond of the given compound is cleaved in the presence of an acid catalyst like HCl or H2SO4. This results in the formation of a carboxylic acid and an alcohol. The carboxylic acid formed is butanoic acid, which is a 4-carbon carboxylic acid. The alcohol formed is ethanol, which is a 2-carbon alcohol. Therefore, the correct answer to this question is butanoic acid and ethanol.
When a compound undergoes hydrolysis in an acidic environment, it typically breaks down into its constituent components. Based on the given answer choices, it appears that the compound in question is an ester formed between butanoic acid and ethanol.
During hydrolysis, this ester reacts with water in the presence of an acid to break the ester bond and produce the original components, which are butanoic acid and ethanol. Therefore, the correct answer is "butanoic acid and ethanol."
To know more about Compound visit :
https://brainly.com/question/14117795
#SPJ11
Which of the essential nutrients is listed in the course as actually a group of micronutrients?
Answers
Vitamins and Minerals
Micronutrients, often known as vitamins and minerals, are essential for healthy growth, illness prevention, and overall well-being. Micronutrients, apart from vitamin D, are not generated by the system and must be obtained from food. Even though humans only require trace levels of micronutrients, ingesting the required quantity is critical. Micronutrient deficits can be life-threatening. At least the majority of all children under the age of five suffers from deficiencies of vitamins and minerals.
Despite the fact that humans only require modest levels of micronutrients, it's crucial to eat the suggested quantity. Devastating repercussions can result from micronutrient deficits. Around the world, at least 50% of children under the age of five have vitamin and mineral deficiencies.
To know more about micronutrients refer to https://brainly.com/question/6974286
#SPJ4
how do catalysis affect the energy of reactions?
A. they lower the activation energy required for the reactions to take place.
B.They act as fuel that burns and provides energy for the reactions
C.The act as low-energy materials that are used to make the products of the reactions
D.They absorb excess energy that would otherwise stop reactions from happening
I NEED HELP ASAP!!!!
Answers
hence, your answer is A
How does the idea of quantized energy apply to Bohr’s atomic model?
Answers
Answer:the electrons can possess only certain discrete energy values; values between those quantized values are not permitted.
Explanation:Both involve a relatively heavy nucleus with electrons moving around it, although strictly speaking, the Bohr model works only for one-electron atoms or ions.
Calculate the energy associated with photon of light having a wavelength 6000A˚. [h=6.624×10−²⁷erg sec]
Answers
The energy of a photon with a wavelength of 6000\(A^0\) can be calculated using Planck's equation and the given value of Planck's constant.
When calculating the energy of a photon, we can use the equation E = hc/λ, where E is the energy, h is Planck's constant, c is the speed of light, and λ is the wavelength. Substituting the given values into the equation, we have \(E = (6.624*10^(^-^2^7^) erg sec)(3*10^1^0 cm/sec)/(6000A^0)\).
To simplify the calculation, we need to convert the wavelength from angstroms (\(A^0\)) to centimeters (cm). Since \(1A^0 = 10^(^-^8^)\) cm, the wavelength becomes \(6000A^0 = 6000*10^(^-^8^) cm\).
Substituting this value into the equation, we have \(E = (6.624*10^(^-^2^7^) erg sec)(3*10^1^0 cm/sec)/(6000A^0)\)\(/(6000*10^(^-^8^) cm)\).
After canceling out the units, we can simplify the equation further and calculate the value of E. The resulting energy will be in ergs, which is the unit commonly used in this context.
Learn more about Planck's constant here:
https://brainly.com/question/30763530
#SPJ11
How would antibodies against NT receptors affect the neuromuscular junction?
Answers
Antibodies against nicotinic acetylcholine receptors (nAChR), present at neuromuscular junction (NMJ), can affect function of junction by interfering with normal signaling between nerve and muscle.
How would the antibodies against NT receptors affect neuromuscular junction?Antibodies against nicotinic acetylcholine receptors (nAChR), which are present at neuromuscular junction (NMJ), can affect the function of junction by interfering with normal signaling between nerve and muscle.
At NMJ, the nerve terminal releases acetylcholine (ACh), which binds to nAChR on muscle cell membrane, leading to depolarization of muscle cell and muscle contraction. If antibodies bind to nAChR, they can block or reduce the number of available receptors for ACh, leading to decrease or even complete loss of the normal muscle response to nerve stimulation.
This can result in muscle weakness, fatigue, and even paralysis, depending on the severity of antibody binding and amount of functional nAChR remaining at the NMJ.
To know more about neuromuscular junction, refer
https://brainly.com/question/17076742
#SPJ1
Using the AHf and the Sº values from the table, estimate the minimum temperature at which magnetite can be reduced to iron by graphite. Fe3O4(s) + 2C (s, graphite) → 2CO2 (g) + 3Fe (s) AH (kJ/mol) Sº (J/K.mol) -1118.4 146.4 Substance Fe3O4(s) C(s, graphite) CO2(g) Fe (s) 0 5.7 -393.5 213.7 247.6 O Magnetite will be reduced by carbon at any temperature. 54.3°C 2.34°C 1012°C Magenetite cannot be reduced by carbon at any temperature. Question 21 1 pts What is the enthalpy change for the chemical reaction in question 20? 0 -142.05 kJ/mol O-311.41 kJ/mol 0-538.14 kJ/mol 311.41 kJ/mol
Answers
Since both the enthalpy and the entropy are positive magnetite will be reduced by carbon at any temperature. Option A
What is the required temperature?We know that we can only know the temperature at which the reduction of the iron III oxide with carbon would take place by the use of the enthalpy and the entropy of formation of the substance.
The enthalpy of the reaction is;
Enthalpy of products - Enthalpy of reactants
= [2(-393.5) + 3(0)] - [(-1118.4) + 2(0])
= (-784) + 1118.4
= 334.4 kJ
The entropy of the reaction is;
[2(213.7) + 3(247.6)] - [146.4 + 2(5.7)]
(427.4 + 742.8) - (146.4 + 11.4)
=1170.2 - 157.8
= 1012.4 kJ
Learn more about enthalpy:https://brainly.com/question/3393755
#SPJ1
how many moles is 8.34 x 1022 molecules of NH3
Answers
What signs of a chemical reaction did you observe during the lab? Check all that apply.
color change
temperature change
mass change
formation of a gas
formation of a solid
formation of a liquid
Answers
Answer:
1, 4, 5
Explanation:
1 - Color Change
4 - Formation of Gas
5 - Formation of Solid
(correct on ed)
Answer: A, D , E
Explanation:
Consider the phase diagram for sulfur shown here. The rhombic and monoclinic states are two solid states with different structures.
a. Below what pressure does solid sulfur sublime?
b. Which of the two solid states of sulfur is most dense?
Answers
The pressure of solid sulfur sublime is 0.27mm.
The Monoclinic solids has a greater density than the rhombic one.
What is density?Density is a measure of the amount or mass per unit volume of a particular substance. Density is mathematically defined as mass divided by volume. Density varies for each element in the periodic table and is also affected by environmental conditions such as temperature and atmospheric pressure. Density is also affected by other substances that cause chemical reactions.
Therefore, if the pressure is less than 0.027 mm of mercury, one sublimation of the solid is seen. And if you look at the line here, it's a positive slope. This suggests that the 1s on the right side of the Mono Klinik body are denser.
To know more about density click-
https://brainly.com/question/26364788
#SPJ1
Lead is melted and is poured into a mold to make fishing weights
Answers
Lead is melted and is poured into a mold to make fishing weights. This is an example of a physical change.
Chemical or physical changes are both possible. Anything that has mass and takes up space is referred to as "matter." It has both physical and chemical qualities and is composed of small particles.
A sort of change known as physical change occurs when the physical characteristics of matter change. Physical changes include those in color, odor, solubility, and the condition of matter, among others.
The chemical makeup or content of matter are not altered after a physical transformation. The internal makeup is unaffected as molecules rearrange themselves during this transformation. The chemical attribute is unaffected by a physical change.
To know more about chemical change
https://brainly.com/question/2591189
#SPJ4
The complete question is
Lead is melted and is poured into a mold to make fishing weights. This is an example of a________change.
1) physical
2)chemical
During the light reactions water is oxidized to O2. Where do the hydrogens go?
A. Used in the reduction of NADP+
B. Used in the synthesis of ATP by chemiosmosis
C. Diffuse out of the chloroplast and unite with O2 to form H2O
D. A and B
E. A, B and C
Answers
During the light reactions water is oxidized to O2. hydrogen go to Used in the reduction of NADP+.
The photolysis process, sometimes referred to as the light reaction, occurs when light is present. Typically, it occurs in the chloroplasts' grana. Pigment molecules are present in photosystems. One of the key pigments in plants that actively participates in light-related processes like photosynthesis is chlorophyll. In the chloroplast of the mesophyll cells of the leaves, a light-dependent process takes place. The stacked disc-like structures known as thylakoids make up the double-membraned cell organelles known as chloroplasts. The membrane of these thylakoids contains the pigment chlorophyll, which is necessary for the process and is where the light reaction takes place.
learn more about molecules Refer:brainly.com/question/29755819
#SPJ4
Keq for H2 +I2 double sided arrow 2HI is 32.0 at equilibrium H2=I2=.400M what is the concentration of HI?
Answers
The concentration of HI is 25.6 M.
The equilibrium constant expression for the reaction H₂ + I₂ ⇌ 2HI is Keq = [HI]² / [H₂][I₂]. We are given that Keq = 32.0 at equilibrium, and that the initial concentrations of H₂ and I₂ are both 0.400 M. Let x be the equilibrium concentration of HI.
Using the equilibrium constant expression and the given values, we can set up the following equation:
32.0 = x² / (0.400)(0.400)
Solving for x, we get:
x = √(32.0 x 0.400 x 0.400)
x = 25.6 M
Therefore, the concentration of HI at equilibrium is 25.6 M.
To learn more about concentration, here
https://brainly.com/question/10725862
#SPJ1
explain how a motorcar engine produces nitrogen oxides
Answers
Answer: combustion causes a chemical reaction between nitrogen and oxygen in the engine.
Explanation:
Nitrogen oxides are produced in combustion processes, partly from nitrogen compounds in the fuel, but mostly by direct combination of atmospheric oxygen and nitrogen in flames. Nitrogen oxides are produced naturally by lightning, and also, to a small extent, by microbial processes in soils.
Answer:
when fuels are burned in vehicle engines high temperatures are reached. at these high temperature nitrogen and oxygen from the air combine to produce nitrogen
what is the name of the base that has the formula ca(oh)2 ? spell out the full name of the compound.
Answers
The name of the base that has the chemical formula Ca(OH)₂ is calcium hydroxide.
What is calcium hydroxide and how do you know the full name of the compound?Calcium hydroxide is an inorganic compound that is obtained by the action of water on calcium oxide. Calcium hydroxide is also called slaked lime. This compound is used as a constituent of mortars, plasters, and cement, and as an industrial alkali.
Usually, a molecular compound is composed of two or more nonmetal elements. Ca(OH)₂ consists of one calcium atom, two oxygen atoms, and two hydrogen atoms. As a result, the full name of the chemical formula is calcium hydroxide.
Learn more about chemical formula here: https://brainly.com/question/27017277
#SPJ4
Calculate the number of atoms in 0.25 moles of manganese?
Answers
1.5 × 10²³ atoms Mn
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Atomic Structure
Using Dimensional AnalysisAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Explanation:Step 1: Define
0.25 mol Mn
Step 2: Identify Conversions
Avogadro's Number
Step 3: Convert
Set up: \(\displaystyle 0.25 \ mol \ Mn(\frac{6.022 \cdot 10^{23} \ atoms \ Mn}{1 \ mol \ Mn})\)Multiply: \(\displaystyle 1.5055 \cdot 10^{23} \ atoms \ Mn\)Step 4: Check
Follow sig fig rules and round. We are given 2 sig figs.
1.5055 × 10²³ atoms Mn ≈ 1.5 × 10²³ atoms Mn