Electrophilic aromatic substitution reactions have various applications in organic chemistry. They are commonly used to introduce functional groups onto aromatic rings, synthesize pharmaceuticals, produce dyes, and create complex organic molecules.
In organic chemistry, electrophilic aromatic substitution reactions are crucial tools for attaching new functional groups to aromatic rings. In these reactions, an electrophile replaces a hydrogen atom on an aromatic molecule. The end output can be used in a variety of different sectors.
Pharmaceutical synthesis is one area in which electrophilic aromatic substitution is used. Chemists can change the solubility, reactivity, and bioavailability of medicinal compounds by selectively adding functional groups to aromatic rings. This enables the creation of fresh medication candidates or the advancement of current ones.
The manufacture of dyes is an additional use. Due to their conjugated systems, aromatic compounds with particular functional groups can display bright hues. Colorful dyes used in textiles, inks, and other industries are produced through the introduction of chromophores onto aromatic rings using electrophilic aromatic substitution processes.
Additionally, it is essential for the synthesis of complex organic compounds to undergo electrophilic aromatic substitution processes. Chemists can create complex chemical structures with particular functions by carefully swapping various locations on an aromatic ring. This makes it possible to synthesize natural substances, sophisticated compounds, and materials with specific qualities.
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HELPHELPHELPHELPHELPHELPHELP
Answer:
C
Explanation:
increasing T (knowledge of direct proportion and Inverse proportion)
which of the following is true of carbon? select all that are correct. group of answer choices it can form a maximum of four covalent bonds with other elements. it can form a maximum of three covalent bonds with other elements. it is highly electronegative. it can form both polar and nonpolar bonds. it can only form polar molecules.
Based on the given options, the following statements are true of carbon: It can form a maximum of four covalent bonds with other elements and It can form both polar and nonpolar bonds.
Carbon is an element with atomic number 6, meaning it has six protons in its nucleus. It has four valence electrons, which are the electrons involved in bonding with other atoms.
Carbon's electron configuration allows it to form four covalent bonds by sharing its valence electrons with other atoms. This property is known as tetravalency and is a fundamental characteristic of carbon.
Additionally, carbon can form both polar and nonpolar bonds depending on the atoms it is bonded to and the electronegativity difference between them.
When carbon bonds with atoms of similar electronegativity, such as hydrogen, the bond is nonpolar because the electrons are shared equally. However, if carbon bonds with atoms of higher electronegativity, such as oxygen or nitrogen, the bond becomes polar due to the unequal sharing of electrons.
In summary, carbon can form a maximum of four covalent bonds with other elements due to its tetravalent nature. It is not highly electronegative itself but can form both polar and nonpolar bonds depending on the atoms it is bonded to. Therefore, the correct statements are:
It can form a maximum of four covalent bonds with other elements.
It can form both polar and nonpolar bonds.
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What is the final concentration of a solution prepared by using 75.0 mL of 18.0 M H2SO4 to prepare 500. mL of solution?
A) 2.35 M
B) 8.33×10-3 M
C) 15.7 M
D) 2.70 M
E) 1.20 M
The required correct answer is D) 2.70 M
The final concentration of a solution prepared by using 75.0 mL of 18.0 M H2SO4 to prepare 500. mL of solution is 2.70 M. Here's how to calculate it:We will use the formula:M1V1 = M2V2where:M1 = initial molarityV1 = initial volumeM2 = final molarityV2 = final volumeGiven that M1 = 18.0 M, V1 = 75.0 mL, and V2 = 500. mL. We can find M2 as follows:M1V1 = M2V218.0 M x 75.0 mL = M2 x 500. mLM2 = (18.0 M x 75.0 mL)/500. mL= 2.70 MTherefore, the final concentration of the solution is 2.70 M. The correct option is D.
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If the temperature remains constant and pressure is INCREASED on gas, what will happen to the volume?
The volume will increase.
The volume will decrease.
The volume will not change.
The volume will randomly increase and decrease, and keep doing this.
Answer:
I believe the volume should increase.
(Please help 15 points the assignment is late) (multiple questions) (everything is virtual task )
Part 1 What do you think will happen when an effervescent tablet is placed in the water under each inverted glass?
Part 2 Note the changes in the water level and the air space in both glasses, and write down your observations.
Part 3 Did your prediction match your observation?
Part 4. When a substance easily dissolves in a liquid, it has high solubility in that liquid. When a substance does not easily dissolve in a liquid, it has low solubility in that liquid. Solubility of a gas in water describes how well the liquid can “hang on” to gas, instead of releasing it into the air. Based on the results of your experiment, do you think that CO2 has a higher solubility in hot water or cold water? Why?
Part 5 Soda pop is carbonated with CO2. Mark puts one bottle of soda pop in the refrigerator and leaves the other out in the hot sunlight. After one hour, he opens both bottles. Which bottle will likely have more fizzing and bubbles? Why?
Part 6 One result of climate change is that ocean temperatures are increasing. If the temperatures continue to rise, what effect will that have on the oceans’ ability to retain CO2? How might this change affect the atmosphere?
The dissolution of gases in water is exothermic therefore oceans will dissolve less CO2 as their temperatures rise.
What is effervescence?
The term effervescence refers to the rise of a gas in a system or simply put, it is the evolution of gas. When an effervescent tablet is placed in the water under each inverted glass, a gas will rise in each glass.
The air space in the hot glass is greater than the air space in the cold glass We can see that the gas has a lower solubility in hot water than in cold water. This is because, solubility of gases is exothermic.
The bottle that is left in the hot sun will have more fizzing because the CO2 does not dissolve owing to the higher temperature.
The rise in ocean temperature means that the oceans will dissolve less CO2 in the future and reduce the CO2 holding capacity of the oceans.
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PLEASE HELP ME NO LINKS
Answer: I don’t think the answer is A or C. Maybe B.
The word chemosynthesis means
the synthesis of organic compounds by bacteria or other living organisms using energy derived from reactions involving inorganic chemicals, typically in the absence of sunlight.
Explanation:
Which is a characteristic of a physical change?
a
The chemical bonds in the substance are unchanged.
b
The change cannot be seen.
c
The molecules all move at the same speed.
d
The substance has reacted with another substance.
How many grams are in 2.33 x 1023 molecules of Fe203?
61.9 grams
2.33x10^23 molecules (159.7 g Fe2O3/6.02x10^23 molecules) = 61.9 g
Complete and balance the following redox equation in acidic solution using the smallest whole number coefficients. What is the coefficient of SnO₂ in the balanced equation? Sn + HNO₃ → SnO₂ +NO₂ +H₂O a. 2
b. 1
c. 4
d. 3
The coefficient of SnO₂ in the balanced equation is c. 4.
To balance the redox equation in acidic solution, we need to ensure that the number of atoms of each element and the total charge are balanced on both sides of the equation.
By assigning appropriate oxidation numbers to each element and considering the changes in oxidation states, the balanced equation is as follows:
Sn + 4HNO₃ → SnO₂ + 4NO₂ + 2H₂O
In the balanced equation, the coefficient of SnO₂ is 4, indicating that 4 molecules of SnO₂ are produced. This balanced coefficient ensures that the number of tin (Sn) atoms and oxygen (O) atoms are equal on both sides of the equation. Therefore, the correct answer is c. 4.
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2.50 Kilojoule (2.5 Kj) is the same amount of energy in calories?
A) 598 cal.
B) 2720 cal.
C) 0.598 cal.
D) 105 cal.
2.50 Kilojoule (2.5 Kj) is the same amount of energy in calories as (A) 598 cal.
To convert kilojoules (Kj) to calories, you can use the conversion factor of 1 kilocalorie (kcal) = 4.184 kilojoules (Kj).
Here, 2.50 Kilojoules (2.5 Kj) is the amount of energy, we can convert it to calories as follows:
2.50 Kj * (1 kcal / 4.184 Kj) = 0.598 kcal
Since 1 kilocalorie (kcal) is equal to 1000 calories (cal), we can further convert:
0.598 kcal * 1000 cal/kcal = 598 cal
Therefore, the same amount of energy as 2.50 Kilojoules (2.5 Kj) is 598 calories.
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why is it necessary to make sure the stopcock is in the open position and then immediately replace the stopper and syringe assembly in the Erlenmeyer flask after adding the hydrochloric acid to the marble chips?
It is important to keep the stopcock open after adding hydrochloric acid to the marble chips in an Erlenmeyer flask for gas collection and accurate measurement of the carbon dioxide produced during the reaction.
Why is it necessary to make sure the stopcock is in the open position and then immediately replace the stopperBy allowing the gas to escape into the syringe or collection apparatus, the experiment can obtain precise gas volume measurements. Additionally, immediately replacing the stopper and syringe assembly helps prevent gas loss and maintains safety by avoiding the build-up of excessive pressure inside the flask.
These measures ensure the reliable and controlled execution of the experiment while obtaining accurate data.
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30g of Aluminum at 80°c is added to 30g of water at 10°c . Predict
the final temperature of the water
Answer:
the explanation of this 20
Explanation:
20 c
A transition metal complex has a a maximum absorbance of 610.7 nm. What is the crystal field splitting energy, in units of kJ/mol, for this complex? Express your answer using at least three significant figures.
The crystal field splitting energy for the transition metal complex with a maximum absorbance of 610.7 nm is approximately 53.8 kJ/mol.
The absorbance maximum at 610.7 nm corresponds to the energy of the absorbed light, which can be calculated using 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. Rearranging the equation to solve for the crystal field splitting energy (Δ), we get Δ = hc/λ. Plugging in the values, Δ = (6.626 x 10^-34 J·s * 3.00 x 10^8 m/s) / (610.7 x 10^-9 m). The result is approximately 3.23 x 10^-19 J. To convert this to kJ/mol, we need to multiply by Avogadro's number (6.022 x 10^23) and divide by 1000, giving us a crystal field-splitting energy of approximately 53.8 kJ/mol. This value is obtained by calculating the energy of the absorbed light using 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. By rearranging the equation and plugging in the values, we can determine the crystal field splitting energy, which represents the energy difference between the d-orbitals in the complex.
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3.4
Why is this cocktail not the perfect medication to treat infections by these
bacteria?
Answer:
many bacteria are resistant to penicillin and other β-lactam antibiotics - some bacteria have beta-lactamase enzymes and are able to break down the antibiotics - as a result, many drugs are combined with other drugs that are β-lactamase inhibitors.
Explanation:
Quizlet
A 0.100 M oxalic acid, HO2CCO2H, solution is titrated with 0.100 M KOH. Calculate the pH when 25.00 mL of oxalic acid solution is titrated with 35.00 mL of NaOH. Ka1 = 5.4 × 10−2 and Ka2 = 5.42 × 10−5 for oxalic acid
A 0.100 M oxalic acid, HO₂CCO₂H, solution is titrated with 0.100 M KOH. Calculate the pH when 25.00 mL of oxalic acid solution is titrated with 35.00 mL of NaOH. Ka1 = 5.4 × 10−2 and Ka2 = 5.42 × 10−5 for oxalic acid is 1.94.
Oxalic acid is a dicarboxylic acid with the chemical formula HO₂CCO₂H, with a pKa1 of 1.25 and a pKa2 of 4.14. A titration is a process in which a solution of known concentration is added to a solution of unknown concentration until the equivalence point is reached.
The goal of a titration is to determine the concentration of the unknown solution. A 0.100 M oxalic acid solution is titrated with 0.100 M KOH. The pH is calculated when 25.00 mL of oxalic acid solution is titrated with 35.00 mL of NaOH. Ka1 = 5.4 × 10−2 and Ka2 = 5.42 × 10−5 for oxalic acid. Here is how to calculate the pH when 25.00 mL of oxalic acid solution is titrated with 35.00 mL of NaOH:
Step 1: Calculate the moles of oxalic acid
moles of oxalic acid = concentration x volume
moles of oxalic acid = 0.100 M x 0.025 L
moles of oxalic acid = 0.0025 mol
Step 2: Calculate the moles of NaOH
moles of NaOH = concentration x volume
moles of NaOH = 0.100 M x 0.035 L
moles of NaOH = 0.0035 mol
Step 3: Determine which species is in excess
0.0025 mol of oxalic acid reacts with 0.0025 mol of KOH
0.0010 mol of oxalic acid reacts with 0.0035 mol of KOH
0.0010 mol of oxalic acid is consumed in the reaction
The excess moles of NaOH = 0.0035 - 0.0010 = 0.0025 mol
Step 4: Calculate the concentration of the remaining OH- ions
Concentration of OH- ions = moles of OH- ions / volume
Concentration of OH- ions = 0.0025 mol / 0.060 L
Concentration of OH- ions = 0.0417 M
Step 5: Calculate the concentration of H+ ions
Ka1 = [H+][C₂O₄₂-]/[HC₂O₄-]
5.4 x 10^-2 = x^2 / (0.100 - x)
Assuming that x is much smaller than 0.100, x = [H+] = 0.115 M
Step 6: Calculate the pH
pH = -log[H+]
pH = -log(0.115)
pH = 1.94
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Thallium-201 has a half-life 73 hours. If 4.0 mg of thallium-201 disintegrates over a period of 6.0 days and 2 hours, how many milligrams of thallium-201 will remain?
Answer:
[tex]\huge\boxed{\sf 1.0 \ mg}[/tex]
Explanation:
Half-life = 73 hours
Disintegration period = 6 days 2 hours = (6*24) hours + 2 hours
= 144 hours + 2 hours
= 146 hours
No. of Half lives = Disintegration period / Half-lifeNo. of Half lives = 146 hours / 73 hours
No. of Half lives = 2
Hence, there are 2 half lives passed in 6 days 2 hours.
Amount of thallium-201 left after first half-life:
= 4.0 mg / 2
= 2.0 mg
Amount of thallium-201 left after second half-life:
= 2.0 mg / 2
= 1.0 mg
Hence, the amount of thallium-201 left after 6.0 days and 2 hours is 1.0 mg.
[tex]\rule[225]{225}{2}[/tex]
Hope this helped!
~AH1807Why is it dangerous to have electric appliances near you when you are taking a bath?
Answer:
Because water conducts electricity, so if an electrical current were to meet the water while you're in there taking a bath, you would essentially be surrounded by a huge conductor.
A gaseous mixture contains 5.0 moles of nitrogen and 10.0 moles of helium . What is the total pressure if the temperature is 25 degrees C and the volume is 3.0 L? a) 122 atm
B) 56 atm
d) 2.0 atm
C)3.0 atm
Answer:
A) 122 atm
Explanation:
PV = nRT
Solve for P --> P = nRT/V
n = 10.0 mol + 5.0 mol = 15.0 mol
R = 0.08206 L atm / mol K
T = 25 + 273 = 298 K
V = 3.0
P = (15.0)(0.08206)(298) / (3.0) = 122 atm
Identify the element for this electron configuration: 1s^2 2s^22p^63s^23p^63d^104s^24p.
The element for the given electron configuration 1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁰ is Chromium (Cr).
An element's electron configuration is a numeric representation of how the electrons are distributed among the various energy levels and orbitals. It may provide valuable insights into an element's chemical properties and reactions. To comprehend this electron configuration, we'll go through each sublevel from the lowest to the highest energy level: 1s², 2s², 2p⁶, 3s², 3p⁶, 3d¹⁰, 4s², and 4p⁰.
The 1s sublevel contains two electrons (1s²). In the second energy level, the 2s sublevel contains two electrons (2s²), and the 2p sublevel contains six electrons (2p⁶). The 2p sublevel has three orbitals, each of which may accommodate two electrons. As a result, the 2p sublevel contains six electrons. The third energy level contains 3s² and 3p⁶ sub levels. The 3s sublevel contains two electrons, while the 3p sublevel contains six electrons.
Both sublevels' orbitals may accommodate two electrons. The 3d sublevel is also in the third energy level. It contains ten electrons (3d¹⁰). The 3d sublevel has five orbitals, each of which may hold two electrons. As a result, the 3d sublevel has ten electrons. The 4s sublevel is in the fourth energy level. It contains two electrons (4s²). Finally, the 4p sublevel contains zero electrons. As a result, the electronic configuration 1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁰ is that of Chromium (Cr).
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Atomic Size: Determine which of the following element pairs is the larger one
1. Carbon or Fluorine
2. Iodine or Fluorine
3. Krypton or Argon
4. Hydrogen or Potassium
if you mix equal volumes of 1 m hf and 1 m koh, is the resulting solution acidic , basic, or neutral?
The resulting solution is neutral when equal volumes of 1 M HF and 1 M KOH are mixed.
When equal volumes of a strong acid and a strong base are mixed, the resulting solution is neutral. In this case, 1 M HF (hydrofluoric acid) and 1 M KOH (potassium hydroxide) are both strong acids and bases, respectively.
When the HF and KOH react, they undergo a neutralization reaction:
HF + KOH → KF + H2O
The reaction between a strong acid and a strong base forms a salt (KF in this case) and water. Since KF is a neutral salt and water is neutral, the resulting solution will be neutral.
When equal volumes of 1 M HF and 1 M KOH are mixed, the resulting solution is neutral.
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The coffee shop near the local college normally sells 10 ounces of roasted coffee beans for $10. But the shop sometimes puts the beans on sale. During some sales, it offers "33 percent more for free." Other weeks, it takes "33 percent off" the normal price. After reviewing the shop's sales data, the shop's manager finds that "33 percent more for free" sells a lot more coffee than "33 percent off." Are the store's customers making a systematic error? Which is actually the better deal? a. No, they are not making a systematic error because "33 percent more for free" is the better deal. b. Yes, they are making a systematic error because "33 percent off" is the better deal. c. This cannot be determined from the information given.
The “33 percent more for free” deal is better than the “33 percent off” deal. This is because the “33 percent more for free” deal gives you 13.3 ounces of coffee for $10, while the “33 percent off” deal gives you only 6.7 ounces of coffee for $6.67
For the “33 percent more for free” deal:
10 dollars for 10 ounces of coffee
13.3 ounces of coffee for 10 dollars (33% more)
Price per ounce = 10/13.3 = $0.75 per ounce
For the “33 percent off” deal:
10 dollars for 10 ounces of coffee
6.7 ounces of coffee for $6.67 (33% off)
Price per ounce = 6.67/6.7 = $0.99 per ounce
So, the “33 percent more for free” deal is better than the “33 percent off” deal because you get more coffee for your money.
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An organism that makes or creates their own food?
A. Consumer
B. Producer
C. Decomposer
I think producer
option is A
Answer:
B. Producer
Explanation:
A producer is normally a type of plant which is food for the animals. Decomposers are things that decompose dead living things into nutrients and etc. Consumers are the ones who normally feed on producers in the food web and are small animals.
Help me pleaseeeeeeeeeee
Answer:
I think A I hope it's A
Explanation:
hsjsjakkska
Both the appearance and cooking times of food items are affected by the way a piece of food is:
Select one:
a. examined.
b. tenderized.
c. purchased.
d. cut.
Answer:
D.
cut.
Explanation:
Both the appearance and cooking times of food items are affected by the way a piece of food is cut. Thus option D is correct.
what are the types of food ?
Food has an important role in both culture and cuisine of every country, Different types of food combine to form culinary delights which can bring people together
Food is obtained from both plants and animals where Plants are the primary producers in the food pyramid and all organism directly or indirectly obtain food from plants.
Herbivorous animals get their food from their plant ecosystem where Some animals, obtain food by hunting other animals while others depend on decaying matter of plants and animals which are called decomposers like bacteria, fungi.
Food offers variety forms depend upon climatic conditions and availability and depend on the different factors like Physical determinants ,Biological determinants, Economical determinants.
Thus option D is correct.
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Mg(s) + HCl (l) --> H2 (g) +MgCl2 (s) A student conducted an experiment with 2g of magnesium and 3 mL of 6M hydrochloric acid. Equal volumes (3mL) of hydrochloric acid and magnesium strips (2g) were put into each tube. What are the reactants in this reaction?
Answer: Do you have an image so I can solve it?
WILL RATE BRAINLIST
Your friend works in a bookstore where lab books for science are assembled. Each lab book uses 2 covers, 50 sheets of lined paper, 25 sheets of graph paper and 3 staples. Her inventory includes 150 covers, 7500 sheets of lined paper and 3000 sheets of graph paper and 250 staples. What is the “limiting reactant?” How many complete lab books can be made? How much of each of the other reactants remain in excess?
Answer:
The limiting reactant is the covers.
We are left with 3750 sheets of lined paper, 1125 sheets of graph paper and 25 staples.
Explanation:
the reaction is:
B - book
C - cover
Sl = sheet of lined paper
Sg - sheet of graph paper
St - staple
1B = 2C + 50Sl + 25Sg + 3St
We have covers for 150/2 = 75 books
We have lined paper for 7500/50 = 150 books
We have graph paper for 3000/25 = 120books
We have Staples for 250/3 = 83.(3) books, so for 83 books as we cannot make 1/3 of a book.
Because we only have covers for 75 books, covers are the limiting reactant.
After making 75 books we are left with:
0 covers
7500 - 75*50 = 3750 sheets of lined paper
3000 - 75*25 = 1125 sheets of graph paper
250 - 75*3 = 25 staples
The limiting reactant should be the covers.
We are left with 3750 sheets of lined paper, 1125 sheets of graph paper, and 25 staples.
Calculation of the limiting reaction:
The reaction should be like:
B - book
C - cover
Sl = sheet of lined paper
Sg - sheet of graph paper
St - staple
Now the equation should be
1B = 2C + 50Sl + 25Sg + 3St
We have covers for 150/2 = 75 books
We have lined paper for 7500/50 = 150 books
We have graph paper for 3000/25 = 120books
We have Staples for 250/3 = 83.(3) books, so for 83 books as we cannot make 1/3 of a book.
Now the left should be
7500 - 75*50 = 3750 sheets of lined paper
3000 - 75*25 = 1125 sheets of graph paper
250 - 75*3 = 25 staples
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how is liming a lake similar to a doctor prescribing medicine for a patient?
.Rank the following compounds in order of increasing viscosity at a given temperature. CH3OH, CH3CH3, H2C=O
A) H2C=O < CH3CH3 < CH3OH
B) CH3CH3 < H2C=O < CH3OH
C) CH3OH < CH3CH3 < H2C=O
D) H2C=O < CH3OH < CH3CH3
The correct answer is D) H2C=O < CH3OH < CH3CH3Explanation:Viscosity is the measure of the resistance of a liquid to flow.
It is the ratio of shear stress to shear rate, which is a measure of how fast the fluid is moving between the plates. It can be measured in different units such as poise or centipoise.The viscosity of a liquid is affected by the attractive forces between the molecules, which depend on the type of molecules and their intermolecular forces. The stronger the intermolecular forces, the more viscous the liquid.In this case, CH3OH (methanol), CH3CH3 (ethane), and H2C=O (acetone) are the compounds to be ranked. Methanol is a polar molecule with hydrogen bonding and has a higher viscosity than ethane, which is nonpolar and has weak van der Waals forces. Acetone is a polar molecule with dipole-dipole interactions that are intermediate between methanol and ethane. The order of increasing viscosity is therefore H2C=O < CH3OH < CH3CH3.
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Select the correct answer.
What data points do we combine to make the integrated rate law?
a) initial concentration and time
B) concentration at some later time, time, and rate constant
C) initial concentration, concentration at some later time, and time
D) initial concentration, concentration at some later time, time, and rate constant
Answer:
b???
Explanation:
Answer:
Pretty sure it A.
Explanation:
I just thought that cause what exactly does 'some later time' mean?