Enter your answer in the provided box. What is the original molarity of an aqueous solution of ammonia (NH,) whose pH is 11.30 at 25°C? K for NH3 1.8 x 10-5 0.013 M
Answers
The original molarity of an aqueous solution of ammonia (NH,) whose pH is 11.30 at 25°C is 0.012 M.
The original molarity of the aqueous solution of ammonia can be calculated using the pH and the Kb (base dissociation constant) of NH3. Since NH3 is a weak base, we use the following equation:
Kb = Kw/Ka = [NH4+][OH-]/[NH3]
Where Kb is the base dissociation constant, Kw is the ion product constant (1.0 x 10^-14), Ka is the acid dissociation constant (5.6 x 10^-10), [NH4+] is the concentration of the ammonium ion, [OH-] is the concentration of hydroxide ion, and [NH3] is the original molarity of NH3.
From the pH of 11.30, we know that [OH-] is 10^-2.30 M = 5.01 x 10^-13 M. Plugging in these values, we get:
1.8 x 10^-5 = (1.0 x 10^-14)/(5.6 x 10^-10) = [NH4+][OH-]/[NH3] = (5.01 x 10^-13) [NH4+]/[NH3]
Solving for [NH3], we get:
[NH3] = [NH4+]/(5.01 x 10^-13 / 1.8 x 10^-5) = [NH4+]/2.785
We also know that [NH3] + [NH4+] = 0.013 M, so:
[NH4+] = 0.013 M - [NH3]
Substituting into the previous equation, we get:
[NH3] = (0.013 M - [NH3])/2.785
Solving for [NH3], we get:
[NH3] = 0.012 M
Therefore, the original molarity of the aqueous solution of ammonia is 0.012 M.
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Related Questions
What will happen if the planet has low degrees of angle of inclination?
Answers
Answer:
Because seasons are caused by the changing angles that sunlight strikes the Earth (due to it's tilted axis), a decrease in tilt would mean less extreme seasons. ... However, less tilt would mean less of a change in angle around the orbit and therefore cooler summers and warmer winters.
The first thing you did after getting home was to check to make sure your pet electron, named "Elecpatra" was safe while you were gone. Last time you saw her, she was looking at you with an adorable face in its content ground state in the mid- region of the 1D infinite well of width L that you carefully created for her. Now that you came back after being gone for a while, she was super excited, enough to be in the 4th excited state! What is the probability that you would find her in the mid region now, between x = 3L/8 and x = 5L/8? x = = 0.250 0.227 0.295 0.205
Answers
The approximate probability of finding Elecpatra in the mid-region between x = 3L/8 and x = 5L/8 is 0.250.
To calculate the probability of finding Elecpatra in the mid-region between x = 3L/8 and x = 5L/8, we need to determine the probability amplitude associated with that region.
The probability amplitude can be found by examining the wave function of Elecpatra in the 4th excited state of the 1D infinite well.
In the 1D infinite well, the wave function for the nth excited state can be expressed as:
ψ(x) = sqrt(2/L) * sin((n * π * x) / L)
Since Elecpatra is in the 4th excited state, n = 4. We can now substitute the values into the wave function:
ψ(x) = sqrt(2/L) * sin((4 * π * x) / L)
To find the probability amplitude for the mid-region between x = 3L/8 and x = 5L/8, we integrate the absolute square of the wave function over that region. The probability amplitude is the square root of the result.
P = Integral [3L/8 to 5L/8] |ψ(x)|^2 dx)
Calculating the integral and simplifying the expression, we find:
P = sqrt(2/π)
Approximating π as 3.14, we can evaluate the expression:
P ≈ sqrt(2/3.14)
P ≈ 0.250
Therefore, the approximate probability of finding Elecpatra in the mid-region between x = 3L/8 and x = 5L/8 is 0.250.
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(60 points + brain list)
Which is the configuration of an atom in the ground state?
A)
2-8-2
B)
2-6-1
C)
2-7-2
D)
2-7-3
Answers
Answer:
Ground state means when n = 1
and here the electronic configuration is 2:8:2
Score of 0.500 M solution of a weak acid,[H+] was measured as 4.02× 10 to the -3rdM, what is the dissociation constant?
Answers
Answer:
Explanation:
1.0
⋅
10
−
7
Explanation:
Start by writing a balanced chemical equation for the partial ionization of the acid
HA
(aq]
+
H
2
O
(l]
⇌
A
−
(aq]
+
H
3
O
+
(aq]
Notice that you have
1
:
1
mole ratios across the board. For every mole of acid that ionizes in aqueous solution, you get one mole of its conjugate base and one mole of hydronium ions,
H
3
O
+
.
In other words, the equation produces equal concentrations of conjugate base and hydronium ions.
Now, you can use the pH of the solution to calculate the equilibrium concentration of the hydronium ions.
pH
=
−
log
(
[
H
3
O
+
]
)
⇒
[
H
3
O
+
]
=
10
−
pH
In your case, the pH of the solution is equal to
4
, which means that you'll have
[
H
3
O
+
]
=
10
−
4
M
By definition, the acid dissociation constant,
K
a
, will be equal to
K
a
=
[
A
−
]
⋅
[
H
3
O
+
]
[
HA
]
The expression for the acid dissociation constant is written using equilibrium concentrations. So, if the reaction produced a concentration of hydronium ions equal to
10
−
4
M
, it follows that it also produced a concentration of conjugate base equal to
10
−
4
M
.
Because the initial concentration of the acid is considerably higher than the concentrations of the conjugate base and hydronium ions, you can approximate it to be constant.
This means that the acid dissociation constant for this acid will be
K
a
=
10
−
4
⋅
10
−
4
0.100
=
1.0
⋅
10
−
7
This is the underlying concept behind an ICE table
HA
(aq]
+
H
2
O
(l]
⇌
A
−
(aq]
+
H
3
O
+
(aq]
I
0.100
0
0
C
(
−
x
)
(
+
x
)
(
+
x
)
E
0.100
−
x
x
x
Here
x
represents the equilibrium concentration for the conjugate acid and hydronium ions. Since you know that
x
=
10
−
4
, you will have
K
a
=
10
−
4
⋅
10
−
4
0.100
−
10
−
4
Once again, you can use
0.100
−
10
−
4
=
0.0999
≈
0.100
to get
K
a
=
10
−
8
0.100
=
1.0
⋅
10
−
7
What is the density of a sample of a substance with a volume of 120ml
and a mass of 90g?
Answers
Answer:
The answer is 0.75 g/mLExplanation:
The density of a substance can be found by using the formula
\(density = \frac{mass}{volume} \\ \)
From the question
mass = 90 g
volume = 120 mL
We have
\(density = \frac{90}{120} = \frac{9}{12} = \frac{3}{4} \\ \)
We have the final answer as
0.75 g/mLHope this helps you
Which of the following is not a work practice control when working with corrosive materials:Group of answer choicesUse corrosive resistance containers such as glass or plasticWhen diluting, add water to acid, never vice versaStore acids separate from basesWhen pouring large volumes of corrosive liquids, use a fume hoodUtilize personal protective equipment when working with corrosive materials
Answers
Answer:
H
Explanation:
because the thing goes there and that goes there
The work practice control that is not directly related to working with corrosive materials is Utilize personal protective equipment when working with corrosive materials.
The correct option is D.
While personal protective equipment (PPE) is an important safety measure when working with corrosive materials, it is not specifically a "work practice control." The other options mentioned are examples of work practice controls that involve specific actions and procedures to mitigate the risks associated with handling corrosive materials.
Work practice controls are measures or practices that are put in place to minimize exposure to hazards in the workplace. The options like using corrosive-resistant containers, storing acids separately, adding water to acid while diluting, and using a fume hood when pouring large volumes are all examples of work practice controls aimed at reducing the risks associated with working with corrosive materials.
Hence , D is the correct option
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What two molecules are used in the synthesis of sphingosine?.
Answers
Palmitoyl-CoA and serine are the two molecules that are used in the synthesis of sphingosine.
A sphingolipid molecule, sphingosine is synthesized from two molecules, palmitoyl-CoA and serine. Sphingosine is a component of the plasma membrane, and it is involved in cell signaling processes that regulate cell growth, differentiation, and apoptosis.A sphingolipid is a lipid that is composed of sphingosine. A long-chain amino alcohol, sphingosine is synthesized from two molecules, palmitoyl-CoA and serine.
In summary, the two molecules that are used in the synthesis of sphingosine are palmitoyl-CoA and serine.
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Write a complete, balanced chemical equation where tin metal reacts with aqueous hydrochloric acid to produce tin(II) chloride and hydrogen gas. Include states.
From the equation, which element is oxidized, and which element is reduced?
Answers
Answer:
Zn(s)+2HCl(aq)→ZnCl2(aq)+H2(g)
Explanation:
The net reaction is Z n ( s ) + 2 H + ( a q ) → Z n 2 + ( a q ) + H 2 ( g ) The C l − ions are spectators - they don't change.
Q.10 Fats and oils Unsaturated fats and oils contain at least one carbon to carbon double bond. These double bonds react with bromine water which changes colour from orange to colourless Plan an experiment that could be carried out to compare samples of sunflower oil, olive oil and butter to find out which of these contains the largest number of carbon to carbon double bonds You are provided with common laboratory apparatus and an organic solvent to dissolve the fats and oils
Answers
Based on the results obtained, the sample with the shortest time taken for the color change to occur contains the largest number of carbon to carbon double bonds.
What is Saturated Fat?
Saturated fat is a type of fat in which all the carbon atoms in the fatty acid chains are bonded to hydrogen atoms, leaving no double bonds between the carbon atoms. This results in a straight and rigid molecular structure that allows the fat molecules to pack tightly together, leading to a solid or semi-solid consistency at room temperature. Saturated fats are commonly found in animal products, such as meat and dairy, as well as in some plant-based sources like coconut and palm oil. A diet high in saturated fats has been linked to an increased risk of heart disease and other health problems.
The sample with the largest number of carbon to carbon double bonds will react the fastest with the bromine water, resulting in the quickest color change from orange to colorless. Therefore, the sample with the shortest time taken for the color change to occur will contain the largest number of carbon to carbon double bonds.
Therefore, the sample that contains the most carbon to carbon double bonds can be determined by comparing the times taken for the color change to occur in each sample.
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What is the mass number of 199F?
Answers
Answer:
fluorine
Explanation:
hope it helps
why does the hydrogen gas need to flow continuously for a while before starting the heating process?
Answers
In the laboratory, hydrogen gas is used as fuel for various purposes, including heating. In order to start the heating process, it is necessary to allow the hydrogen gas to flow continuously for a while. This is because there may be air or other gases present in the hydrogen gas pipeline that can affect the heating process.
When the hydrogen gas is allowed to flow continuously for a while, the air or other gases are purged from the pipeline, which improves the quality of the hydrogen gas. This ensures that there is no interference with the heating process, which could otherwise lead to inaccurate results.The continuous flow of hydrogen gas is essential because if it is not allowed to flow for a while, air or other gases can cause damage to the burner or other equipment used for heating. The air or other gases can cause an explosion, which can result in severe injury or death.In conclusion, the hydrogen gas needs to flow continuously for a while before starting the heating process to remove any air or other gases from the pipeline. This improves the quality of the hydrogen gas, ensures accurate results, and prevents damage to the equipment. It is important to follow safety protocols when using hydrogen gas to prevent any accidents.For such more question on heating process
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What happens to the glucose molecule during the process of cellular respiration?
It gets broken down.
It forms oxygen.
It builds muscles.
It uses up energy.
Answers
Answer:
it's broken down into carbon dioxide and water
Explanation:
The answer is A. It gets broken down.
Emily found a piece of metal. She doesn't know what kind of metal it is. What might she measure in lab to find out what
type of metal it is? Is this a physical or chemical property?
Answers
Answer: Emily can measure the density of the piece of metal to find out what it is. Density is a physical property.
Explanation:
The density of a substance can be found by dividing its mass by its volume. No chemical reaction is involved in measuring the mass nor the volume; therefore, density is a physical property.
A student creates a model of a closed ecosystem by filling a glass tank half
full with water, then adding 10 snails and two small aquatic plants. The next
day, all the snails are dead. What is the most likely cause of their death?
A. The rates of cellular respiration and photosynthesis in the tank
were both too high.
B. The rates of cellular respiration and photosynthesis in the tank
were both too low.
O C. The rate of cellular respiration in the tank was much higher than
the rate of photosynthesis.
D. The rate of photosynthesis in the tank was much higher than the
rate of cellular respiration.
SUBMIT
e
PREVIOUS
Answers
Answer:
C. The rate of cellular respiration in the tank was much higher than
the rate of photosynthesis
Explanation:
In nature, cellular respiration and photosynthesis are opposite metabolic reactions. Cellular respiration, which is the process of releasing energy, requires oxygen while photosynthesis, which is the process of manufacturing foods by green plants, releases oxygen into the atmosphere. The two equations are as follows:
Photosynthesis:
6CO2 + 6H2O → C6H1206 + 6O2 (oxygen released)
Respiration:
C6H1206 + 6O2 (oxygen used) → 6CO2 + 6H2O
According to this question, 10 snails and two small aquatic plants were added to a closed glass tank half full with water. It was observed that all the snails died. This is most likely due to the fact that the rate of cellular respiration in the tank was much higher than the rate of photosynthesis.
In other words, the usage of oxygen via cellular respiration was much higher than the release of oxygen via photosynthesis.
Answer:
1. Snails carry out respiration only
2. Aquatic plants carry out both respiration and photosynthesis Although the aquatic plants can absorb carbon dioxide and release oxygen through photosynthesis, the amount of snail is much more than that of the aquatic plants.
During night time,the absence of light prevent the plants from carrying out photosynthesis. No oxygen is released at this time. There is a net release of carbon dioxide in the closed system and hence the snail died of suffocation.
What gives a pant cell a rigid shape?
A: Chloroplast
B: Vacuole
C: Cell wall
D: Cell membrane
Help me please
Extra points & brainlest
Answers
Answer:
Cell Wall
Explanation:
In plant cells, the cell wall is rigid the outer structure that protects the plant cell.
What is true when a reaction has reached equilibrium?
The reaction is faster in the forward direction.
The reaction has stopped.
The reaction rate is equal in both directions.
The reaction is faster in the reverse direction.
Answers
Which of the following is the primary medium for beach erosion?
ice
gravity
wind
water
Answers
Answer:
Water is the primary erosion
hope it helps :)
why is OH on the outside of the lewis structure for methanol?
Answers
In the Lewis structure of methanol (CH3OH), the OH group is placed on the outside because it is an important functional group that influences the chemical properties and reactivity of the molecule.
The Lewis structure is a representation of a molecule that shows the arrangement of atoms and valence electrons. In methanol, carbon (C) is the central atom bonded to three hydrogen (H) atoms and one oxygen (O) atom. The oxygen atom forms a single bond with carbon and also has two lone pairs of electrons.
The placement of the OH group (hydroxyl group) on the outside of the Lewis structure is significant because it determines the chemical behavior of methanol. The OH group consists of an oxygen atom bonded to a hydrogen atom and represents the presence of an alcohol functional group.
In organic chemistry, functional groups are specific arrangements of atoms within a molecule that give rise to characteristic chemical reactions and properties. The presence and position of functional groups can greatly influence the behavior and reactivity of a compound. In the case of methanol, the hydroxyl group provides the molecule with its characteristic properties.
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in active transport particles primarily flow ___________________ with the help of atp-hydrolysis.
Answers
In active transport particles primarily flow against the concentration gradient with the help of ATP-hydrolysis.
This process is driven by the hydrolysis of ATP, which supplies the energy needed for the movement of molecules against the concentration gradient. The hydrolysis of ATP releases energy, which is used to power the active movement of molecules across the membrane.
This is done by using proteins that act as pumps and enable the passage of molecules into and out of the cell.
The process of active transport is essential in maintaining cellular homeostasis, allowing cells to absorb and expel molecules and ions as needed
The sodium-potassium ATPase is an active transporter, meaning it requires energy to move solutes across a membrane. Specifically, when ATP is hydrolyzed, or broken down, at the active site of the transporter, a conformational change occurs that allows for the transport of solutes.
This transport occurs against the concentration gradient, meaning that the solutes are moving from a higher concentration to a lower concentration. The ATPase uses the energy from the hydrolysis of ATP to move the solutes across the membrane, and the solutes are then released on the other side of the membrane in a process known as cotransport.
In this way, the ATPase can move solutes in an energy-dependent manner, allowing cells to maintain their internal environment.
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which quantum number does not give information about an individual orbital?
Answers
Answer:
the spin quantum number.
In a new compound, it is found that the central carbon atom is sp2 hybridized. This implies that.
Answers
If the central metal ion is sp² hybridized in the new atom, it means that bond of carbon are formed by hybridization of 2 s orbitals and 1 p orbital.
Hybridization means that there is not a singular orbital, there is a new orbital which is forced by the hybridization of the old orbital.
It also means that the central carbon atom is an alkene. it will have a double bond.
It will have two sigma bonds and one pi bond. The bonding in the sp² orbital will have the electron in the s orbital and the p orbital while the carbon atom is in the excited state. Here, s orbitals will be forming two sigma bond and p orbital will be forming the pi bond.
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what pressure of carbon dioxide is required to keep the carbon dioxide concentration in a bottle of club soda at 0.10 baretlby
Answers
The partial pressure required to keep the CO2 concentration in a bottle of club soda at 0.10m would be 0.425atm.
Club soda is a manufactured form of carbonated water, commonly used as a drink mixer. Sodium bicarbonate, potassium sulfate, potassium bicarbonate, potassium citrate, or sodium citrate is artificially added to replicate constituents commonly found in natural mineral waters.
Club soda is one of the many carbonated water in which carbon dioxide gas has been pressurized under some conditions and dissolved. Usually the carbonation process is artificially (carbon is added to water) done and other ingredients added onto it. These ingredients include salt such as sodium citrate, potassium carbonate or potassium sulfate, basically added to create a distinct taste that separates club soda from any other carbonated water. Unlike other type of water, club soda is purely calorie free (no amount of sugar is added).
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after getting a cut why is it important to wash it
Answers
Answer:
so no germs get in the cut an cause an infection
Explanation:
It's important to wash and disinfect a cut to prevent an infection and to make it heal.
An impure sample of potassium hydrogen phthalate was titrated to determine the percent composition KHP. What is the percentage of potassium hydrogen phthalate if 2.81 g of the mixture required 35.61 mL of 0.152 mol/L NaOH to reach the end point
Answers
For an impure sample of potassium hydrogen phthalate, the percentage of potassium hydrogen phthalate is
m'=39.3%
What is the percentage of potassium hydrogen phthalate if 2.81 g of the mixture required 35.61 mL of 0.152 mol/L NaOH to reach the end point?Generally, the equation for the mol base is mathematically given as
mol base = M*V
mol base = 0.152*35.61
mol base = 5.41272 mmol
In conclusion
mass = mmol/1000*MW
m== 5.41272 /1000*204.22
m= 1.1053 g of KHP
Hence, m'=39.3%
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Given the following cell notation Mg(s)∣Mg2+(aq)∥Cu2+(aq)∣Cu(s)
determine the species oxidized, species reduced, and the oxidizing agent and reducing agent, without writing the balanced reactions, and calculate the standard cell potential.
Answers
So, from the cell notation:
Species oxidized: Mg(s)
Species reduced: Cu²⁺(aq)
Oxidizing agent: Cu²⁺(aq) (copper ions)
Reducing agent: Mg(s) (magnesium)
In the given cell notation: Mg(s)∣Mg²⁺(aq)∥Cu²⁺(aq)∣Cu(s)
The species on the left side of the double vertical line (∥) represents the anode, where oxidation occurs. The species on the right side represents the cathode, where reduction occurs.
Species oxidized: Mg(s) (the solid magnesium)
Species reduced: Cu²⁺(aq) (the aqueous copper ions)
Oxidizing agent: Cu²⁺(aq) (copper ions) - It accepts electrons from the magnesium, causing it to be reduced.
Reducing agent: Mg(s) (magnesium) - It loses electrons, causing it to be oxidized.
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Need help now !! Which biome will a biologist visit to see reindeer and wolves that live near a region with lots
of pine trees? (1 point)
O a desert
a taiga
O a tundra
O a tropical rain forest
Answers
Carbon-14 decays to Nitrogen - 14 with a half-life 5730 years.
You found a shell buried in sedimentary layers, which has about 12.5% of its original 14 C
left. Determine the age of the shell.
I NEED HELP PLEASE!!!
Answers
The age of the shell can be determined by using the half-life of Carbon-14, which is 5730 years, and the fact that the shell has 12.5% of its original 14C left.
The shell is approximately 17,190 years old.
Carbon-14 is a radioactive isotope that decays over time. When an organism dies, it stops taking in carbon-14, and the carbon-14 in its body begins to decay into nitrogen-14. The half-life of carbon-14 is the time it takes for half of the carbon-14 in a sample to decay.
In this case, the shell has 12.5% of its original 14C left. This means that 87.5% of the original 14C has decayed into nitrogen-14. We can use the half-life of carbon-14 to determine how long it would take for 87.5% of the 14C to decay.
One half-life of carbon-14 is 5730 years. Therefore, two half-lives would be 2 x 5730 years = 11,460 years. Three half-lives would be 3 x 5730 years = 17,190 years, and so on.
To find the age of the shell, we can use the formula:
age = number of half-lives x half-life of carbon-14
If 87.5% of the 14C has decayed, then 12.5% is left. This means that 1/8th of the original 14C is left. One half-life of carbon-14 is the time it takes for half of the 14C to decay, so if 1/8th is left, then three half-lives have passed.
Therefore, the age of the shell can be calculated as:
age = 3 x 5730 years = 17,190 years
Long Answer: The age of the shell can be determined by using the concept of radioactive decay and the half-life of Carbon-14.
Carbon-14 is a radioactive isotope of carbon that decays over time. When an organism dies, it stops taking in carbon-14, and the carbon-14 in its body begins to decay into nitrogen-14. The rate of decay of carbon-14 is constant, and it is measured by its half-life.
The half-life of carbon-14 is the time it takes for half of the carbon-14 in a sample to decay. This means that if we know the original amount of carbon-14 in a sample and the amount of carbon-14 that is left, we can calculate how many half-lives have passed and use this information to determine the age of the sample.
In this case, the shell has 12.5% of its original 14C left. This means that 87.5% of the original 14C has decayed into nitrogen-14. We can use the half-life of carbon-14 to determine how long it would take for 87.5% of the 14C to decay.
One half-life of carbon-14 is 5730 years. Therefore, two half-lives would be 2 x 5730 years = 11,460 years. Three half-lives would be 3 x 5730 years = 17,190 years, and so on.
To find the age of the shell, we can use the formula:
age = number of half-lives x half-life of carbon-14
If 87.5% of the 14C has decayed, then 12.5% is left. This means that 1/8th of the original 14C is left. One half-life of carbon-14 is the time it takes for half of the 14C to decay, so if 1/8th is left, then three half-lives have passed.
Therefore, the age of the shell can be calculated as:
age = 3 x 5730 years = 17,190 years
In conclusion, the shell is approximately 17,190 years old.
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Help please
What is the equation for density?
O D= m
OD=
m
m
D=
>le Els -
OD=ž
= { mu?
Answers
Answer:
It is this below
Explanation:
P = m/v
Can anyone help w/ this chem problem plz
Answers
Answer:
26
Explanation:
A radioactive substance decays continuously according to the formula A = le^kt, where A is the final amount, I is the initial amount, k is a constant, and t is the time in years. If 70 grams of the substance decays to 25 grams in 8 years, determine the value of k.
Select one:
a. -0.1287
b. -0.4472
c. 0.5708
d. 0.1287
Answers
The value of k is approximately -0.1287. The correct answer is option a. -0.1287
To determine the value of k in the radioactive decay formula A = \(le^kt\), we can use the given information:
A = final amount = 25 grams
I = initial amount = 70 grams
t = time = 8 years
We can substitute these values into the formula and solve for k:
A = \(Ie^kt\)
25 = \(70e^k(8)\)
Dividing both sides of the equation by 70:
\(e^k(8)\)= 25/70
Taking the natural logarithm (ln) of both sides to isolate k:
ln\((e^k(8))\) = ln(25/70)
k(8) = ln(25/70)
Dividing both sides by 8:
k = (1/8) × ln(25/70)
Using a calculator to evaluate this expression, we find:
k ≈ -0.1287
Therefore, the value of k is approximately -0.1287.
The correct answer is: a. -0.1287
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