lodine-131 is a radioactive isotope with a half-life of 8 days. The activity of a sample of iodine-131 is
480 Bq. Calculate the activity of the sample after 16 days.
Answers
The activity of the sample after 16 days is 120 Bq.
What is an activity?
The decay of radioactive isotopes follows an exponential decay law. The activity of a radioactive sample is given by:
A(t) = A₀ \(e^{-kt}\)
where:
A₀ = initial activity of the sample
A(t) = activity at time t
k = decay constant
The half-life of iodine-131 is 8 days, so we can use the following equation to find k:
1/2 = \(e^{(-k * 8)}\)
Solving for k:
ln(1/2) = -k * 8
k = ln(2) / 8
Now we can use the activity equation to find the activity of the sample after 16 days:
A(16) = A₀ \(e^{(-k * 16)}\)
We know that the initial activity A₀ is 480 Bq, so:
A(16) = 480 \(e^{(-ln(2)/8 * 16)}\)
A(16) = 480 \(e^{(-2ln(2))}\)
A(16) = 480 * 0.25
A(16) = 120 Bq
Therefore, The decay of radioactive isotopes follows an exponential decay law. The activity of a radioactive sample is given by:
A(t) = A₀\(e^{-kt}\)
where:
A₀ = initial activity of the sample
A(t) = activity at time t
k = decay constant
The half-life of iodine-131 is 8 days, so we can use the following equation to find k:
1/2 = \(e^{(-k * 8)}\)
Solving for k:
ln(1/2) = -k * 8
k = ln(2) / 8
Now we can use the activity equation to find the activity of the sample after 16 days:
A(16) = A₀ \(e^{(-k * 16)}\)
We know that the initial activity A₀ is 480 Bq, so:
A(16) = 480 \(e^{(-ln(2)/8 * 16)}\)
A(16) = 480 \(e^{(-2ln(2))}\)
A(16) = 480 * 0.25
A(16) = 120 Bq
Therefore, the activity of the sample after 16 days is 120 Bq.
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Complete question is: Lodine-131 is a radioactive isotope with a half-life of 8 days. The activity of a sample of iodine-131 is 480 Bq. The activity of the sample after 16 days is 120 Bq.
Related Questions
Under the privacy rule, the following must be included in a patient accounting of disclosures:
A) state-mandated report of a sexually transmitted disease.
B) disclosure pursuant to a patient s signed authorization.
C) disclosure pursuant to a subpoena.
D) disclosure for payment purposes.
Answers
Under the Privacy Rule, the following must be included in a patient accounting of disclosures: A) state-mandated report of a sexually transmitted disease, C) disclosure pursuant to a subpoena, and D) disclosure for payment purposes.
On the other hand, B) disclosure pursuant to a patient's signed authorization is not required to be included in the accounting of disclosures. When a patient provides written authorization for the release of their PHI to a specific individual or entity, it falls under the patient's control and choice. It is not necessary to include these authorized disclosures in the accounting as they are already accounted for through the patient's explicit consent.
In summary, while state-mandated reports, disclosures pursuant to subpoenas, and disclosures for payment purposes are required to be included in the accounting of disclosures, disclosures made based on a patient's signed authorization are not required to be included as they are accounted for separately. Hence, A, C, and, D are the correct options.
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Rhonda watched a video taken by a camera that was lifted into the upper atmosphere by a weather balloon. She saw the balloon pop when it reached a certain height. Afterward, Rhonda wondered what effect the air pressure at high altitudes has on the volume of gas in balloons.
Answers
Answer:
This question is incomplete; the complete part is: What scientific practice is Rhonda performing?
The answer is ASKING A QUESTION FROM AN OBSERVATION
Explanation:
The SCIENTIFIC METHOD is used for scientific investigations. The scientific method is composed of sequential steps which scientific investigations follow. The steps are:
- Asking a question/Make an observation
- Formulating a hypothesis
- Testing the hypothesis
- Analysing the result
- Conclusion
Asking a scientific question is done after making an observation about an occurrence. In this question, Rhonda wondered what effect the air pressure at high altitudes has on the volume of gas in balloons after watching a video taken by a camera that was lifted into the upper atmosphere by a weather balloon. This illustrates that Rhonda is ASKING A QUESTION FROM AN OBSERVATION.
after the reactions are complete, suppose you have found that the reaction with 2-fluoro-5-nitropyridine was faster than the reaction with 2-bromo-5-nitropyridine. what is the most likely explanation for this observation?
Answers
The intermediate is stabilised by fluorene electronegativity, which removes the electrons from the meisenheiner complex's negative charge, allowing the process to proceed more quickly.
What is fluorene ?The chemical molecule known as fluorene, also known as 9H-fluorene, has the formula (C6H4)2CH2. It produces white crystals with a distinctive, aromatic smell akin to naphthalene. Its name comes from the violet fluorescence it emits. It is made from coal tar for commercial use.Because the Meisenheiner complex, a tetrahedral-like intermediate with a negative charge on the nitrogen of the pyridine ring, is produced by the nucleophilic attack of the benzyl amine. By stabilising the intermediate and removing the electrons from the meisenheiner complex's negative charge, fluorene electronegativity speeds up the reaction.Fluorene can cause skin and eye irritation and burns. White crystalline plates make up fluorene. It serves as a chemical intermediary as well as being employed in resinous goods and colours. Because HHAG and EPA have mentioned fluorene, it is listed on the Hazardous Substance List.To learn more about fluorene refer :
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Which elements are most vigorous and which elements are least vigorous. (a) sodium and iodine. (b) lithium and iodine. (c) potassium and fluorine. (d) potassium and bromine. (e) sodium and bromine
Answers
The elements that are most vigorous would be (c) potassium and fluorine.
The elements that are the least vigorous would be (d) potassium and bromine
Which elements are reactive ?Potassium is a metal, less reactive than sodium but more reactive than lithium, and fluorine is a highly reactive nonmetal, so both elements would be considered vigorous.
Sodium is a highly reactive metal and bromine is a nonmetal, less reactive than iodine but more reactive than chlorine, so both elements would be considered vigorous but not as much as other options.
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What does the nucleus of an atom do to its own electrons? To the electrons of a nearby atom?
Answers
An atom is made up of energy levels that contain electrons which are negatively charged and the nucleus which contains neutrons and protons that are negatively charge .
Due the positive charge of the nucleus of an atom, an atom always want to attract its electrons and keep them near it however it weakly attracts the other electrons of a nearby atom.
How is radiation different from conduction?
SELECT AN ANSWER
Radiation is the transfer of heat through molecular contact, and conduction is the transfer of energy by waves.
Radiation is the transfer of energy by waves, and conduction is the transfer of heat through contact with air.
Radiation is the transfer of energy by waves, and conduction is the transfer of heat through molecular contact.
Radiation is a type of heat transfer in the atmosphere as opposed to conduction, which does not transfer energy.
Answers
Answer:
Radiation is the transfer of energy by waves, and conduction is the transfer of heat through contact with air.
Explanation:
Conduction is the transfer of thermal energy through direct contact. Radiation is the transfer of thermal energy through thermal emission.
How do I balance this?
Answers
C12H22O11 (s) + 12O2 (g) ⇒ 12CO2 (g) + 11H2O (g)
why do the noble gases have relatively low electron affinities?
Answers
Answer:
Because noble gases have a full octet, their ionization energies are actually quite high. Electron affinity is the amount of energy released when an electron is added to a neutral atom. Because noble gases have stable electron configurations, they have very low electron affinities.
Explanation:
Answer:
Noble gases have a stable outer shell
Explanation:
this tool calculates the value required in a single cell
Answers
The tool that calculates the value required in a single cell to produce a desired result within a related cell is Goal Seek.
Goal Seek is the appropriate tool for determining the value needed in a specific cell to achieve a desired outcome in a related cell. It allows users to set a target value for a specific cell and then calculates the input value required in another cell to produce the desired result.
This tool is particularly useful for performing "reverse calculations" where the desired outcome is known, but the input value needs to be determined. Goal Seek iteratively adjusts the input value until the desired result is achieved in the target cell.
On the other hand, Solver is used for complex calculations involving constrained optimization, One-or-two variable data table is used to analyze the impact of varying inputs on a formula, and Scenario Manager is used for comparing different scenarios.
However, for calculating the value required in a single cell to produce a desired result, Goal Seek is the appropriate choice.
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What are the free radicals?
What are the negative health consequences of high amount of free radical in the system? (3 pts)
What are the antioxidants? (1.5 pts)
Answers
Free radicals are highly reactive molecules or atoms that have unpaired electrons in their outer shells.
Negative health consequences of a high amount of free radicals in the system include, Oxidative Stress, Inflammation, Cellular Damage.
Antioxidants are substances that can neutralize or counteract the damaging effects of free radicals.
Free radicals are highly reactive molecules or atoms that have unpaired electrons in their outer shells. They are formed as natural byproducts of various biological processes in the body, such as metabolism, immune response, and environmental factors like pollution, radiation, or smoking. Free radicals are unstable and seek to stabilize themselves by oxidizing other molecules in the body, leading to a chain reaction of damage to cells, proteins, and DNA.
Negative health consequences of a high amount of free radicals in the system include:
Oxidative Stress: Excessive free radicals can cause oxidative stress, which is an imbalance between the production of free radicals and the body's antioxidant defenses. This can result in damage to cellular components and contribute to the development of chronic diseases, including cancer, cardiovascular diseases, neurodegenerative disorders, and aging.
Inflammation: Free radicals can trigger and perpetuate inflammation in the body. Chronic inflammation is associated with various health conditions, including arthritis, asthma, diabetes, and autoimmune disorders.
Cellular Damage: Free radicals can damage cell membranes, proteins, and DNA, leading to mutations, cell dysfunction, and impaired cellular processes. This can disrupt normal cell function and contribute to the development of diseases.
Antioxidants are substances that can neutralize or counteract the damaging effects of free radicals. They help inhibit or reduce the oxidation of other molecules by donating an electron to stabilize the free radicals without becoming free radicals themselves. Antioxidants can be naturally occurring compounds found in fruits, vegetables, whole grains, nuts, and seeds, as well as synthetic substances. Some common antioxidants include vitamins C and E, beta-carotene, selenium, and various phytochemicals. Consuming a diet rich in antioxidants or supplementing with antioxidants can help protect against oxidative stress and mitigate the negative health consequences associated with high levels of free radicals.
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I need someone to help me awnser is you have a min
Answers
The introduction of DDT (dichlorodiphenyltrichloroethane) and other ____________ pesticides into agriculture after World war II changed pest control and food production
Answers
The introduction of DDT (dichlorodiphenyltrichloroethane) and other synthetic pesticides into agriculture after World War II changed pest control and food production. What are pesticides? Pesticides are chemicals that are used to kill pests. Pests are defined as any organism that interferes with human activity, like insects that damage crops or rodents that spread disease. Synthetic pesticides were created after World War II.
They include DDT (dichlorodiphenyltrichloroethane) and other synthetic pesticides. What was the impact of the introduction of synthetic pesticides? The introduction of synthetic pesticides like DDT had a major impact on pest control and food production. These pesticides allowed for increased crop yields and better control over insect and rodent populations.
However, they also had negative effects on the environment and human health. Pesticides can contaminate soil and water, harm beneficial organisms, and lead to the development of pesticide-resistant pests. They can also cause health problems for humans, including cancer, reproductive issues, and neurological damage.
The use of synthetic pesticides continues to be a controversial issue, with advocates for both sides of the argument. Some argue that they are necessary for efficient food production, while others argue that they are too harmful to be used safely.
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1) For the precipitation reaction of calcium oxalate below, the Ks = 3.7x10 Note: For this question, do not apply the small x approximation. A) If excess calcium oxalate were added to 100.0 mL of pure water, what concentration of calcium ions and oxalate ions would be expected when the solution is saturated? B) If 1.00 mg of calcium chloride were then added to the mixture (assume no solution volume change and complete dissolution and dissociation of CaCl2), what would be the expected concentrations of calcium ions and oxalate ions once equilibrium is reestablished? Ca2+(aq) + C2042(aq) ⇄ CaC204(s)
Answers
A) In precipitation reaction when the solution is saturated, the expected concentration of both calcium ions and oxalate ions would be approximately 0.0192 mol/L.
B) After equilibrium is reestablished, the expected concentrations of calcium ions and oxalate ions are approximately 2.498 × 10⁻⁴ mol/L and 0.0192 mol/L, respectively.
To answer the given questions about the precipitation reaction of calcium oxalate, let's break it down into two parts:
A) The concentration of calcium ions and oxalate ions in the saturated solution can be determined when an excess amount of calcium oxalate is added to 100.0 mL of pure water.
Since excess calcium oxalate is added, it means that the solution will contain more calcium oxalate than what can dissolve. At saturation, the solution is in equilibrium with the solid calcium oxalate.
Let's assume the concentration of calcium ions and oxalate ions in the saturated solution is represented by "x" (in mol/L).
The equilibrium expression for the reaction is:
Ks = [Ca²⁺][C₂O₄²⁻]
Given that the equilibrium constant Ks = 3.7 × 10⁻⁴, we can set up the equation:
3.7 × 10⁻⁴ = x * x
Solving for "x," we find:
x = √(3.7 × 10⁻⁴) ≈ 0.0192 mol/L
Therefore, when the solution is saturated, the expected concentration of both calcium ions and oxalate ions would be approximately 0.0192 mol/L.
B) If 1.00 mg of calcium chloride (CaCl2) were added to the mixture, what would be the expected concentrations of calcium ions and oxalate ions once equilibrium is reestablished?
Since calcium chloride (CaCl₂) dissociates completely into calcium ions (Ca²⁺) and chloride ions (Cl⁻) in solution, the addition of 1.00 mg of CaCl₂ will result in the addition of 1.00 mg of calcium ions.
First, we need to convert the mass of calcium ions from mg to mol:
1.00 mg = 0.001 g
0.001 g / (molar mass of Ca²⁺) = 0.001 g / 40.08 g/mol ≈ 2.498 × 10⁻⁵ mol
Since the solution volume is assumed to be unchanged, the concentrations of calcium ions and oxalate ions will change but not the molar amounts.
The concentration of calcium ions is the molar amount (2.498 × 10^(-5) mol) divided by the total solution volume (100.0 mL or 0.100 L):
Concentration of calcium ions = (2.498 × 10⁻⁵ mol) / 0.100 L ≈ 2.498 × 10⁻⁴ mol/L
The concentration of oxalate ions remains the same as in part A since the addition of calcium chloride does not affect the concentration of oxalate ions.
Therefore, after equilibrium is reestablished, the expected concentrations of calcium ions and oxalate ions are approximately 2.498 × 10⁻⁴ mol/L and 0.0192 mol/L, respectively.
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A person rides in an elevator.
What is the equal and opposite force for the Earth's force of gravity pulling down on the person as
described by Newton's third law?
Answers
Answer:
Normal force
Explanation:
normal force always perpendicularly points away from a surface
Normal force is the equal and opposite force for the Earth's force of gravity pulling down on the person as described by Newton's third law.
What is force?Force is defined as a cause which is capable of changing the motion of an object. It can cause an object which has mass to change it's velocity. It is also simply a push or a pull . It has both magnitude as well as direction.Hence, it is a vector quantity.
It has SI units of Newton and is represented by'F'.Newton's second law states that force which acts on an object is equal to momentum which changes with time. If mass of object is constant, acceleration is directly proportional to net force acting on an object.
The concepts which related to force are thrust and torque .Thrust increases the velocity of an object and torque produces change in rotational speed of an object.
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Given the following equation:
5F2 (g) + 2NH3 (g) -> N2Fa (g) +6HF (g)
how many grams of hf form from the reaction of 22.2g of nh3 with an excess of fluorine?
Answers
The balanced chemical equation is: 5F2 (g) + 2NH3 (g) -> N2Fa (g) + 6HF (g)
From the equation, we can see that the molar ratio between NH3 and HF is 2:6, or 1:3. This means that for every 2 moles of NH3 reacted, 6 moles of HF will be produced.
First, we need to convert the given mass of NH3 to moles using its molar mass. The molar mass of NH3 is 14.01 g/mol for nitrogen (N) and 3.01 g/mol for hydrogen (H), giving a total molar mass of 14.01 + 3.01 x 3 = 17.04 g/mol.
Moles of NH3 = 22.2 g / 17.04 g/mol = 1.303 mol
Since the molar ratio between NH3 and HF is 1:3, the moles of HF produced will be 3 times the moles of NH3 reacted.
Moles of HF = 1.303 mol x 3 = 3.909 mol
Finally, we can calculate the mass of HF formed using its molar mass, which is 19.00 g/mol for fluorine (F) and 1.01 g/mol for hydrogen (H), giving a total molar mass of 19.00 + 1.01 = 20.01 g/mol.
Mass of HF formed = Moles of HF x Molar mass of HF
Mass of HF formed = 3.909 mol x 20.01 g/mol = 78.24 g
So, 78.24 grams of HF will form from the reaction of 22.2 grams of NH3 with an excess of fluorine.
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a. what is the hybridization of the central atom in cse2?
Answers
The orbital hybridization of the central carbon atom in CSe2 is sp.
In chemical bonding, atomic orbitals may be combined to form appropriate hybrid orbitals suitable for bonding. The orbitals that combine during hybridization must be close enough in energy.
In the compound Cse2, carbon is the central atom bonded to two selenium atoms. The carbon atom in CSe2 is sp hybridized.
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give 10 examples of potential energy converted into kinetic energy
Answers
Answer:
Book on Table
Car at the Hilltop
Falling Objects
Skydiver
Hammering a Nail
Dam Water
Roller Coaster
Stretched Rubber Band
Simple Pendulum
Compressed Spring
Battery
Flashlight
Exothermic Chemical Reaction
Burning of Oil, Gas and Coal
Wind Turbine
Explanation:
have a nice day!
if a solution of sodium bicarbonate is mixed with an equimolar solution of hydrochloric acid, aqueous sodium chloride, water, and carbon dioxide are produced. what is the net ionic equation for this reaction?
Answers
Answer:
the net ionic is
Explanation: CO32-(aq) + 2H+(aq) --> H2O(l) + CO2(g)
The net ionic equation for the given chemical reaction is :CO₃²\(^-\)(aq) + 2 H+(aq) \(\rightarrow\) H₂O(l) + CO₂(g).
What is ionic equation?Ionic equation is defined as a chemical equation which represents electrolytes in aqueous solutions and are expressed as dissociated ions. Ions present in aqueous solutions are stabilized by ion dipole interactions with the water molecules which are present.
An ionic equation can be written for any electrolyte which dissociates and reacts with the polar solvent. In a balanced ionic equation , number and type of atoms on each sides of reaction arrow are same. Even the net charge on both sides of the arrow is same.
Strong acids and bases exist as dissociated ions present in the solution and are written in forms of ions in ionic equation.Weak acids and bases do not dissociate completely and hence are written in the form of molecular formula.
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the indicated gene codes for a protein made up of the amino acid
Answers
Answer:
N/A
Explanation:
Is this a true or false answer or.....?
When following the scientific method, why would asking a subjective question be
an inappropriate part of the procedure?
•A subjective question means it has little or nothing to do with the observation.
•A subjective question would negate any findings from the observation.
•A subjective question is too specific and needs to be simplified to conduct an
experiment.
•A subjective question deals with opinions, morals, and emotions and is not suited
for science.
Answers
The statement 'A subjective question deals with opinions, morals, and emotions and is not suited for science' is the explanation of why a subjective question is inappropriate for the scientific procedure (Option 4).
Why opinions are inaccurate for the scientific method?Opinions are inaccurate for the scientific method because any subjective point of view may bias the process to obtain knowledge, which always must be tested by experimentation.
In conclusion, the statement 'A subjective question deals with opinions, morals, and emotions and is not suited for science' is the explanation of why a subjective question is inappropriate for the scientific procedure (Option 4).
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Most of the volume of an atom is occupied by -
A
protons
B.
empty space
C.
a gas
D.
the nucleus
Answers
Hockey is a sport in which players use hockey sticks to push a puck across smooth ice. At practice one day, three different-colored hockey pucks were sliding on the ice. The green hockey puck has less mass than the black and purple hockey pucks, which have the same mass. A player hit each hockey puck with a stick, but not from the same direction. Use the information in the diagram to answer.
Which puck(s) experienced the strongest force when hit? How do you know?
Answers
Answer:
The purple hockey puck; it takes a stronger force to slow down a more massive object than to speed it up.
Explanation:
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Which of the following ionic compounds would be expected to have the highest lattice energy? A) KI B) KBr C) KCl D) KF
Answers
The ionic compounds that would be expected to have the highest lattice energy is KF>KCl>KBr>KI.
Lattice energy can be defined as the energy required to convert one mole of an ionic solid into gaseous ionic constituents. Alternatively, it can be defined as the energy that must be supplied to one mole of an ionic crystal in order to separate it into gaseous ions in a vacuum via an endothermic process.
As we increase the ion charge variable, lattice energy generally increases. This means that ions with larger charge values will produce ionic compounds with greater lattice energies. In turn, the ions that are possessing weaker charges decrease the lattice energies of their compounds.
Lattice energy is directly proportional to the charge of the ions and inversely proportional to the size of the ions. Thus lattice energy increases as the size of anion decreases.
Therefore the order here would be KF>KCl>KBr>KI.
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What is the measurement from the line of origin to the crest?
A. Trough
B. Amplitude
C. Crest
D. Wavelength
Answers
perform the following mathematical operation and report the answer to the appropriate number of significant figure 16.222-4.99 = [?]
Answers
After performing the mathematical operation the answer to the appropriate number of 16.222-4.99 is 11.232.
What is significant figure?Significant figures are the number of digits that add to the correctness of a value, frequently a measurement. The first non-zero digit is where we start counting significant figures. Determine how many significant digits there are given a range of numbers.
Note that; According to the criteria for significant figure addition, the outcome will have decimal places equal to the lowest of the given values.
We were given the expression 16.222-4.99so that we can perform the sunbstraction and gives the result ot the appropriate signifuicant figure which can be done as :
( 16.222-4.99) = 11.232
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give a reason for the following questions:
1. Silver bromide is stored in a brown colour thick glass bottle
Answers
Silver bromide is stored in a brown colour thick glass bottle in order to regulate the amount of light that enters it.
What is silver bromide used for?Silver bromide is an inorganic compound; the silver salt of hydrobromic acid, AgBr, sometimes used in photographic papers.
Silver bromide is a photosensitive chemical compound that easily undergoes photolytic breakdown. It quickly interacts with light and loses its characteristic by generating bromine gas and silver.
Silver bromide tends to decompose when light falls on it. In order to prevent this, dark colored bottles are used as they restrict the amount of light entering the bottle.
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Chymotrypsin has an α-helix that contains 2.5 turns. Approximately how many amino acids are involved in this helix?A. 20.25B. 9C. 13.5D. 3.75E. 2.5
Answers
Chymotrypsin has an α-helix that contains 2.5 turns. Approximately 9 amino acids are involved in this helix.
What is chymotrypsin?
The pancreas produces chymotrypsin. Chymotrypsinogen is its precursor. By cleaving peptide bonds in locations Arg15–Ile16, trypsin activates chymotrypsinogen and generates –chymotrypsin. The "oxyanion hole" and the hydrophobic "S1 pocket" are the results of the interaction between the aminic group (-NH3+) of the Ile16 residue and the side chain of Asp194. Additionally, chymotrypsin causes its own activation by cleaving at positions 14, 15, 146, and 148 to create -chymotrypsin, which is both more active and stable than -chymotrypsin. A three-polypeptide molecule with disulfide bonds connecting them makes up the final product.To know more about chymotrypsin, click the link given below:
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Certain minerals exclude lead but not uranium from their crystal structure, so when the minerals form they have no lead, only uranium. As time goes on, the uranium decays to lead, so measuring the ratio of lead atoms to uranium atoms allows investigators to determine the ages of the minerals. If a sample of a mineral contains 3 atoms of 207Pb207Pb for every 1 atom of 235U235U, how many years ago was it formed
Answers
Answer:
The answer is "\(1.4 \ \bold{ billion-years}\)".
Explanation:
Using formula:
\(\to N_{Now} = N_{orige}e^{\lambda t} \\\\\)
\(\to\) 1 U atom produces 1 Pb atom after decay.
\(\to\) U's original numbers are now the sum of U counts and Pb counts.
\(\to N_U=(N_U+N_{pb})e^{\lambda Ut}\)
\(\to 1 = (1+3) \ exp[(\frac{-\ln(2)}{t_{(half)}} \times t ]\\\\\to t = [\frac{\ln(4)}{\ln(2)}] \times t_{(half)}\)
\(= 14 \times 10^8 \ \ years\\\\=1.4 \ billion \ \ years\)
what is the ph at the equivalence point in the titration of a 26.1 ml sample of a 0.496 m aqueous hydrocyanic acid solution with a 0.331 m aqueous potassium hydroxide solution?
Answers
The pH at the equivalence point of titration of the 26.1 mL sample of the 0.496 M of the aqueous hydrocyanic acid solution is 0.70.
The chemical equation for the titration is :
HCN + KOH --> H₂O + KCN
The moles of the HCN = 0.496 x 0.0261
The moles of the HCN = 0.010 moles of HCN = moles of the KOH at the equivalence point = 0.010/ 0.331
= 0.0246 L of KOH
At the equivalence point,
The molarity of the solution = 0.010/(0.0261 + 0.0246)
The molarity of the solution = 0.199 M
pH = - log(0.199)
pH = 0.70
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please help me answer this asap
Answers
Answer: the answer is A
Explanation: its alot to put down