a. Since 38 is greater than 20, the approximation is valid.
b. Since 24 is greater than 20, the approximation is valid.
c. Since 20 is equal to 20, the approximation is borderline and may or may not be valid.
What is 5% rule?The 5% rule states that an equilibrium concentration can be approximated by its initial concentration if the initial concentration is at least 20 times greater than the equilibrium concentration. Mathematically, this can be expressed as:
initial concentration / equilibrium concentration ≥ 20
(a) For cyanic acid (HCNO), the equilibrium expression is:
HCNO ⇌ H⁺ + CNO⁻
The Ka expression is:
Ka = [H⁺][CNO⁻] / [HCNO]
Using the given pKa value, we can calculate the Ka value:
pKa = -logKa
[tex]Ka = 10^{-pKa} = 4.02 x 10^{-4}[/tex]
Let x be the equilibrium concentration of [H⁺] and [CNO⁻]. Then, at equilibrium, [HCNO] = 0.45 - x. Plugging these into the Ka expression, we get:
4.02 x 10⁻⁴ = x² / (0.45 - x)
Solving for x, we get x = 0.012 M.
Now, we can check if the 5% rule applies:
initial concentration / equilibrium concentration = 0.45 / 0.012 ≈ 38
Since 38 is greater than 20, the approximation is valid.
(b) For hydrazoic acid (HN₃), the equilibrium expression is:
HN₃ ⇌ H⁺ + N₃⁻
The Ka expression is:
Ka = [H⁺][N₃⁻] / [HN₃]
Using the given pKa value, we can calculate the Ka value:
pKa = -logKa
[tex]Ka = 10^{-pKa} = 2.51 x 10^{-5}[/tex]
Let x be the equilibrium concentration of [H⁺+] and [N₃⁻]. Then, at equilibrium, [HN₃] = 0.0077 - x. Plugging these into the Ka expression, we get:
2.51 x 10⁻⁵ = x² / (0.0077 - x)
Solving for x, we get x = 3.22 x 10⁻⁴ M.
Now, we can check if the 5% rule applies:
initial concentration / equilibrium concentration = 0.0077 / 3.22 x 10⁻⁴ ≈ 24
Since 24 is greater than 20, the approximation is valid.
(c) For arsenic acid (H₃AsO₄), the equilibrium expression is:
H₃AsO₄ + H₂O ⇌ H₃O + H₂AsO₄⁻
The Ka expression is:
Ka = [H₃O⁺][H₂AsO₄⁻] / [H₃AsO₄]
Using the given pKa value, we can calculate the Ka value:
pKa = -logKa
[tex]Ka = 10^{-pKa} = 6.98 x 10^{-3}[/tex]
Let x be the equilibrium concentration of [H₃O⁺] and [H₂AsO₄⁻]. Then, at equilibrium, [H₃AsO₄] = 1.5 - x. Plugging these into the Ka expression, we get:
6.98 x 10⁻³ = x² / (1.5 - x)
Solving for x, we get x = 0.074 M.
Now, we can check if the 5% rule applies:
initial concentration / equilibrium concentration = 1.5 / 0.074 ≈ 20
Since 20 is equal to 20, the approximation is borderline and may or may not be valid. Therefore, we need to use a more accurate method to calculate the equilibrium concentration.
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paolo added 7.9 ml of 4.3 m naoh to 4.6 ml of 0.74 m hcl. calculate the concentration, in units of m, of excess oh- in the resulting solution.
The concentration of excess OH- in the resulting solution is 2.15 M.
To calculate this, the amounts of NaOH and HCl must be determined in moles first. For NaOH, 7.9 mL of a 4.3 M solution is equivalent to 33.87 mmol. For HCl, 4.6 mL of a 0.74 M solution is equivalent to 3.444 mmol.
Since the moles of NaOH is greater than the moles of HCl, the concentration of excess OH- is equal to the moles of NaOH divided by the total volume of the solution. Therefore, the concentration of OH- is equal to 33.87/[(7.9+4.6) mL] = 2.15 M.
To calculate the concentration of excess OH- in the solution, the amount of NaOH and HCl present must be determined in moles first. To do this, the volume and molarity of each reactant is used.
The volume of each reactant is given, as well as the molarity of each reactant. By multiplying the volume of each reactant by its molarity, the moles of each reactant is calculated.
Since the moles of NaOH is greater than the moles of HCl, the concentration of excess OH- is equal to the moles of NaOH divided by the total volume of the solution. This can then be calculated to determine the concentration of excess OH- in the solution.
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11. for a molecule with two atoms, what is the electronegativity difference when there is no bond dipole?
Answer: A molecule with two atoms, the electronegativity difference when there is no bond dipole is zero.
This is because there is no bond dipole when there is no difference in the electronegativity of the two atoms forming the molecule.
What is Electronegativity?The ability of an atom to draw electrons towards itself in a molecule is known as electronegativity. Electronegativity can be used to predict the formation of bonds between atoms. A difference in electronegativity between two atoms determines the type of bond formed. T
he greater the difference in electronegativity, the greater the bond polarity. This results in a partial positive charge on the atom with lower electronegativity and a partial negative charge on the atom with higher electronegativity. Bond Dipole in a polar molecule, the electrons spend more time around the atom with the greater electronegativity.
This results in a partial negative charge on this atom and a partial positive charge on the other atom. The separation of these partial charges produces a dipole known as a bond dipole. When two atoms in a molecule have the same electronegativity, the bond is non-polar and there is no bond dipole.
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Need help with these chemistry quesions about mole ratios. There's an image linked to this. Please help
1) moles Al : moles of HCl
2 : 6
simplifying the ratio;
1 : 3
2) [tex]HCl : AlCl_{3}[/tex]
6 : 2
3 : 1
3) [tex]Al : AlCl_{3}[/tex]
2 : 2
1 : 1
4) [tex]HCl : H_{2}[/tex]
6 : 3
2 : 1
5) [tex]HCl : H_{2}[/tex]
2 : 1
6 : x
x = 6/2
x = 3 moles
6) [tex]HCl : H_{2}[/tex]
2 : 1
12 : x
x = 12/2
x = 6 moles
7) [tex]HCl : H_{2}[/tex]
2 : 1
3 : x
x = 3/2 moles
Astronomers studying the planet of Acer have detected igneous rock under its surface. One astronomer makes a claim that some of the material that this igneous rock formed from used to be in sedimentary rock on the surface of Acer. If the scientist is correct, how could sedimentary rock have become igneous rock?
If the astronomer's claim is correct and igneous rock was formed from material that was originally in sedimentary rock on the surface of Acer, then the process that likely occurred is called "igneous intrusion."
What is Igneous intrusion?Igneous intrusion happens when molten rock, known as magma, is forced into layers of sedimentary rock, which is formed from the accumulation of sediments like sand, mud, or organic matter. As the magma intrudes into the sedimentary rock, it heats up the surrounding rocks and causes them to partially melt and recrystallize. Over time, as the magma cools and solidifies, it forms igneous rock.
The process of igneous intrusion can also cause the sedimentary rock layers to fold or deform, creating features like faults, folds, and uplifts. These changes in the sedimentary rock can be used by geologists to understand the history and geology of a particular region.
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you have 5.00 l salt solution with a molarity of 2.50 mol/l. how much salt solution with a molarity of 20.0 mol/l can be added into the original solution to create a new solution with the molarity of 5.00 mol/l?
Answer : 625 mL of the salt solution with a molarity of 20.0 mol/L can be added to the original solution to create a new solution with a molarity of 5.00 mol/L.
We can use the formula for calculating the molarity of the new solution: M1V1 + M2V2 = M3V3 where, M1 is the molarity of the first solution, V1 is the volume of the first solution, M2 is the molarity of the second solution ,V2 is the volume of the second solution, M3 is the molarity of the final solution and V3 is the volume of the final solution
Now, we will plug in the given values: M1 = 2.50 mol/LV1 = 5.00 LM2 = 20.0 mol/LV2 = 5.00 mol/L, V3 = 5.00 L. We can rearrange the formula to find V2 as = (M3 V3 - M1 V1) / M2 V2 = (5.00 mol/L x 5.00 L - 2.50 mol/L x 5.00 L)/20.0 mol/LV2 = 0.625 L or 625 mL. So we require 0.625 L or 625 ml salt solution.
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A rate constant obeys the Arrhenius equation, the factor A 2.2 x 1013 s and the activation energy being 150. kJ mol. What is the value of the rate constant at 227°C, in 6.7x10-22 s-1 b. 2.1x1013 -1 1.5x101 s 4.7x10-3 s1 a. C.
The rate constant at 227°C is a. 6.7 x [tex]10^{-22}[/tex].
How to find the rate constant of a reaction?The Arrhenius equation states that the rate constant (k) is equal to A × e(-Ea/RT).
Given values: A = 2.2 x 10¹³ s⁻¹, Activation energy (Ea) = 150 kJ/mol, Temperature (T) = 227°C = 500 K.
For this, we need to substitute the given values in the Arrhenius equation as
k = A × e(-Ea/RT)
k = 2.2 x 10¹³ s⁻¹ × e(-150000 J/mol / (8.31 J/mol-K × 500 K))
k = 2.2 x 10¹³ s⁻¹ × e(-30.12)
k = 6.69 x 10⁻¹² s⁻¹
Therefore, the value of the rate constant at 227°C is 6.69 x 10⁻¹² s⁻¹. Hence, option A is the correct answer.
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HELPPPPPPPPPP ME PLEASEEEEEEE AND PLEASEEEEEEE HURRYYYYYY
The formula of an ionic compound must first be charged. After identifying the anion, take note of its symbol and charge. The next step is to unite the two ions to form a electrically neutral molecule.
What takes place whenever an ionic bond is created?An ionic connection forms as a result of the complete passage of certain electrons from one atom to another. An atom loses two or more electrons, forming a negative charges ion called a cation. An atom receives one or more electrons, resulting in the formation of an anion, and negatively charged ion.
What else are ionic compounds and how are they formed?Granules, oxides, hydroxides, sulphides, or the majority all inorganic compounds are examples of ionic compounds. The electrostatic interaction between the negative and positive ions holds ionic solids together. As an illustration, sodium ions draw chloride ions, and chloride ions draw sodium ions.
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Given this equation (linked in screenshot), which of the following is true if 4.53 moles of C6H14 completely reacts with excess oxygen?
A) 0.755 moles CO2 and 0.162 moles H2O will be formed.
B) 27.1 moles CO2 and 31.7 moles H2O will be formed.
C) 12 moles CO2 and 14 moles H2O will be formed.
D) 54.4 moles CO2 and 63.4 moles H2O will be formed.
The correct answer is option D: 54.4 moles CO₂ and 63.4 moles H₂O will be formed when 4.53 moles of C₆H₁₄ completely reacts with excess oxygen.
What is a chemical reaction?
A chemical reaction is a process that leads to the transformation of one chemical substance to another chemical. It involves breaking and forming of chemical bonds between atoms to create new molecules or compounds.
According to the balanced equation given, 2 moles of C₆H₁₄ react with 19 moles of O₂ to produce 12 moles of CO₂ and 14 moles of H₂O.
Therefore, for 4.53 moles of C₆H₁₄ , the amount of O₂ required for complete reaction would be:
(19/2) x 4.53 = 42.9 moles of O₂
Since excess oxygen is present, all the C₆H₁₄ will react, and the number of moles of CO₂ and H₂O produced will be:
CO₂ = 12 x (4.53/2) = 27.2 moles
H₂O = 14 x (4.53/2) = 31.7 moles
Therefore, the answer is D) 54.4 moles CO₂ and 63.4 moles H₂O will be formed.
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PCI3 Draw the Lewis Dot Structure
using many methods I gess I am not good at drawing
soft drink botles are made of pet, a polymer composed of carbon, hydrogen, and oxygen. if 2.8880g of pet is burned in oxygen it produces 1.0000 g h2o and 6.1058g co2. what is the emperical formula of pet
The empirical formula of PET is C4H6O4
PET, or polyethylene terephthalate, is a polymer composed of carbon, hydrogen, and oxygen.
The empirical formula of PET can be determined by burning 2.8880g of PET in oxygen and measuring the amounts of water and carbon dioxide produced.
According to the information given, burning 2.8880g of PET in oxygen produces 1.0000g of H2O and 6.1058g of CO2. This suggests that the empirical formula of PET is C4H6O4.
To break this down further, PET is composed of four carbon atoms (C4), six hydrogen atoms (H6), and four oxygen atoms (O4).
The empirical formula is different from the molecular formula. The empirical formula represents the simplest whole-number ratio of atoms in a molecule, whereas the molecular formula is the actual number of atoms in a molecule.
For example, the molecular formula for PET is C10H8O4, which is a whole-number multiple of the empirical formula.
PET is a polymer composed of carbon, hydrogen, and oxygen.
The empirical formula of PET can be determined by burning 2.8880g of PET in oxygen and measuring the amounts of water and carbon dioxide produced, which suggests that the empirical formula of PET is C4H6O4.
This is different from the molecular formula, which is the actual number of atoms in the molecule.
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g which reaction requires platinum as a catalyst? a. oxidation of an aldehyde or ketone b. reduction of an aldehyde or ketone c. reaction of an aldehyde or ketone with an alcohol d. all of the responses are reactions that are catalyzed by platinum.
The reaction that requires platinum as a catalyst is the B. reduction of an aldehyde or ketone.
This reaction occurs when an aldehyde or ketone is treated with hydrogen gas in the presence of a platinum-based catalyst. The resulting product is alcohol. This reaction is important in the production of alcohols, aldehydes, and ketones from their precursors. The catalyst helps to break the chemical bonds of the molecules and increase the reaction rate.
In addition to being used for the reduction of aldehydes and ketones, platinum can also be used to catalyze the oxidation of an aldehyde or ketone. In this reaction, an aldehyde or ketone is treated with an oxidizing agent, such as oxygen or ozone, in the presence of a platinum-based catalyst. This reaction is used to produce carboxylic acids and esters. Both of these reactions require the use of a platinum-based catalyst, which helps to speed up the reaction rate.
In summary, the reaction that requires platinum as a catalyst is the reduction of an aldehyde or ketone. Platinum can also be used to catalyze the oxidation of an aldehyde or ketone. Both of these reactions are important for the production of alcohols, aldehydes, and ketones from their precursors. Therefore the correct option is B
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A student is making a solution of NaCl in water. If the student uses 7.76 grams of NaCl and enough water to make 5.13 liters of solution, what is the molarity of the student's salt solution?
the ksp of lead (ii) iodide is 7.1x10-9. if it is measured that the lead concentration in solution is 0.0003 m then what is the concentration of iodide in solution?
The Ksp of lead (II) iodide is 7.1x10-9. If it is measured that the lead concentration in the solution is 0.0003 M, then what is the concentration of iodide in the solution is 1.5 x 10-5 M
Given, the Ksp of lead (II) iodide is 7.1x10-9.
The concentration of lead =
Ksp expression of lead (II) iodide is given as,
PbI2 ⇌ Pb2+ + 2I–Ksp = [Pb2+] [I-]2Here, [Pb2+] = 0.0003MIodide.
concentration:
Let’s consider x as the concentration of iodide.
The equilibrium expression of the dissolution of PbI2 is,
PbI2 ⇌ Pb2+ + 2I–Initial: 0 0
Change: -x +x + 2x
At equilibrium: (0-x) (0+ x) (2x)Ksp = [Pb2+] [I-]2= (0.0003) (2x)2= 7.1x10-9x = 1.5 x 10-5 M
The concentration of iodide in solution is 1.5 x 10-5 M.
An alternate method to solve the problem is using the quadratic equation. We can solve the equation as follows,
Ksp = [Pb2+] [I-]2
= (0.0003) (2x)2
= 7.1x10-92x2
= 7.1x10-9/0.00032x2
= 79x = 1.5x10-5 M
Therefore, the iodide concentration in the solution is 1.5 x 10-5 M.
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how are aliphatic compounds defined? multiple choice organic compounds that contain the benzene ring
Answer: Aliphatic compounds are defined as organic compounds that do not contain the benzene ring. They can be divided into three main types: alkanes, alkenes, and alkynes.
What are aliphatic compounds?
Aliphatic compounds are organic compounds that do not contain the benzene ring. Aliphatic compounds can be divided into three main types: alkanes, alkenes, and alkynes. Alkanes are hydrocarbons that contain only single bonds between carbon atoms.
Alkenes are hydrocarbons that contain at least one double bond between carbon atoms. Alkynes are hydrocarbons that contain at least one triple bond between carbon atoms. Aliphatic compounds can be either saturated or unsaturated.
Aliphatic compounds with only single bonds are saturated, whereas those with one or more double or triple bonds are unsaturated. Aromatic compounds are organic compounds that contain the benzene ring. They are unsaturated compounds because they contain alternating double bonds.
They are very stable and are found in many natural substances, such as essential oils, spices, and drugs. Aromatic compounds are also used in the production of plastics, dyes, and other industrial products.
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what is the ph of a calcium hydroxide solution obtained by dissolving 0.40 grams of calcium hydroxide in enough water to obtain 580. ml of solution?
The pH of a calcium hydroxide solution was obtained by dissolving 0.40 grams of calcium hydroxide in enough water to obtain 580. ml of solution is 11.8.
Calcium hydroxide is a strong base that is commonly used in various industries to neutralize acidic wastewater. Calcium hydroxide is commonly known as slaked lime, milk of lime, or hydrated lime. Calcium hydroxide is used in the following industries: steel, petroleum, water treatment, construction, and agriculture.
Here's how to solve the problem: First, find the number of moles of calcium hydroxide in the solution. A number of moles = (mass of solute) ÷ (molar mass)The molar mass of calcium hydroxide is 74.1 g/mol. The number of moles of calcium hydroxide = (0.40 g) ÷ (74.1 g/mol)= 0.00540 mol. Now, calculate the concentration of calcium hydroxide in the solution. Concentration (molarity) = (number of moles of solute) ÷ (volume of solution in L)The volume of the solution in liters is 580 mL or 0.580 L.Concentration (molarity) = (0.00540 mol) ÷ (0.580 L)= 0.00931 MFinally, calculate the pH of the solution using the pOH formula: pOH = -log[OH-]pOH = -log[0.00931]pOH = 2.03pH + pOH = 14pH + 2.03 = 14pH = 11.8Therefore, the pH of the calcium hydroxide solution is 11.8.
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aspirin can be made in the laboratory by reacting acetic anhydride (c4h6o3) with salicylic acid (c7h6o3) to form aspirin (c9h8o4) and acetic acid (c2h4o2) . the balanced equation is
The balanced equation for the formation of aspirin is as follows:
[tex]C_7H_6O_3 + C_4H_6O_3[/tex] → [tex]C_9H_8O_4 + C_2H_4O_2[/tex]
The equation is balanced as there are equal numbers of atoms for each element on both sides.
The chemical formula of aspirin is [tex]C_9H_8O_4[/tex] which is obtained by reacting acetic anhydride ([tex]C_4H_6O_3[/tex]) with salicylic acid ([tex]C_7H_6O_3[/tex]). The reaction also produces acetic acid ([tex]C_2H_4O_2[/tex]) as a by-product.
The balanced chemical equation for the reaction is:
[tex]C_7H_6O_3 + C_4H_6O_3[/tex] → [tex]C_9H_8O_4 + C_2H_4O_2[/tex]
Salicylic acid is an organic acid that is found in various plants, including willow trees and is commonly used to treat pain and fever. Aspirin is a synthetic form of salicylic acid that is commonly used to treat pain and fever as well. It is one of the most widely used drugs in the world today.
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describe the experimental error that could have arisen if your reaction mixture had an oily layer on top when you added the 3 m sulfuric acid.
Experimental error could have arisen if there was an oily layer on top of the reaction mixture when the 3 m sulfuric acid was added.
This could have caused the acid to not mix properly with the reaction mixture, resulting in an incomplete reaction and possibly erroneous results.
To avoid this, the oil layer should be removed before adding the sulfuric acid. This can be done by gently heating the mixture and allowing the oil to evaporate.
The reaction mixture can then be cooled and the sulfuric acid added. Alternatively, the oil layer can be separated by pouring the reaction mixture through a filter.
This will ensure that the sulfuric acid is properly mixed with the reaction mixture, yielding accurate results.
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a hydrogen balloon containing 0.250 moles of hydrogen gas explodes in the presence of oxygen such that all the hydrogen reacts. how much heat is released?
71.5 kJ of heat is released when 0.250 moles of hydrogen gas react with the required amount of oxygen.
When hydrogen reacts with oxygen, it produces water and releases heat. This is an exothermic reaction with a high energy yield, and it is often used in rocket propulsion.
The balanced chemical equation for the reaction between hydrogen and oxygen is:
2H2(g) + O2(g) → 2H2O(l) + energy
From the balanced equation, we can see that 2 moles of hydrogen react with 1 mole of oxygen to produce 2 moles of water. Therefore, the amount of oxygen required to react with 0.250 moles of hydrogen is 0.125 moles.
Assuming the reaction occurs at constant pressure and temperature, we can use the equation:
ΔH = Q / n
where ΔH is the enthalpy change, Q is the heat released or absorbed by the reaction, and n is the number of moles of the limiting reactant (in this case, hydrogen).
The enthalpy change for the combustion of hydrogen gas is -286 kJ/mol. Therefore, the heat released by the reaction of 0.250 moles of hydrogen is:
Q = ΔH x n = -286 kJ/mol x 0.250 mol = -71.5 kJ
Note that the negative sign indicates that the reaction is exothermic and releases heat.
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how many grams each of 5% w/w indomethacin gel and white petrolatum should be mixed to obtain 60 grams of a 3% w/w mixture? g
To obtain 60 grams of a 3% w/w mixture from 5% w/w indomethacin gel and white petrolatum, you need to mix 48.6 grams of the indomethacin gel with 11.4 grams of the white petrolatum.
First, calculate the total weight of the mixture you want to make, which is 60 grams. Then, divide this total weight by the percentage of the final mixture (3%). This gives you the total weight of the individual components: 60/0.03 = 2000 grams.
Next, calculate the weight of each individual component in the final mixture. To do this, multiply the percentage of each individual component with the total weight of the mixture.
The weight of the 5% w/w indomethacin gel in the mixture will be 5/100 x 2000 = 100 grams. And the weight of the white petrolatum in the mixture will be 95/100 x 2000 = 1900 grams. Finally, subtract the weight of the indomethacin gel (100 grams) from the total weight of the mixture (60 grams) to get the weight of the white petrolatum in themixture. This gives you 11.4 grams.
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Do: How many grams are in 2.5 x 1025 CO₂ molecules?
Answer: To solve this problem, we need to use the Avogadro's number, which represents the number of particles (molecules or atoms) in one mole of a substance. The Avogadro's number is approximately 6.022 x 10²³ particles per mole.
First, we need to calculate the number of moles of CO₂ molecules in 2.5 x 10²⁵ molecules:
n = N/N_A
where:
n = number of moles
N = number of molecules
N_A = Avogadro's number
n = 2.5 x 10²⁵ / 6.022 x 10²³
n = 41.56 mol
Next, we can use the molar mass of CO₂ to convert moles to grams. The molar mass of CO₂ is approximately 44 grams per mole.
m = n x M
where:
m = mass in grams
n = number of moles
M = molar mass
m = 41.56 mol x 44 g/mol
m = 1826.24 g
Therefore, there are approximately 1826.24 grams in 2.5 x 10²⁵ CO₂ molecules.
enjoy!
Explanation:
when 5 grams of a nonelectrolyte is added to 30 g of water, the new freezing point is -2.5 deg c. what is the molecular mass of the unknown compound?
The molecular mass of the unknown compound is 3.7 g/mol.
The molecular mass of the unknown compound can be calculated using the formula for freezing point depression, which is:
ΔT = Kf * m
Where Kf is the freezing point depression constant (1.86 K/m),
m is the molality of the solution (moles of solute per kilogram of solvent), and
ΔT is the difference between the freezing point of the pure solvent and the freezing point of the solution.
Plugging in the values given, we get:
-2.5 = 1.86 * m
Solving for m, we get,
m = -2.5 / 1.86
= 1.35 m
Therefore, the molecular mass of the unknown compound can be calculated by dividing the mass of the unknown compound (5 grams) by the molality of the solution (1.35 m).
This gives us a molecular mass of 3.7 g/mol.
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Order the anionic compounds from the most basic to least basic? 3) 1) 2) Magnify Select One Strongest base Second strongest Match With B 3) Weakest base C 2)
The compounds containing anions from the most basic to least basic are:1) B (Strongest base)2) C3) A (Weakest base)The order of basicity of anionic compounds can be determined using the periodic table. The correct answer is B>C>A.
Anions are larger than their corresponding atoms due to the addition of one or more electrons. As a result, anions have lower effective nuclear charges and therefore are more basic than their parent atoms. The larger the anion, the more basic it is. The order of basicity of anionic compounds is as follows:
B > C > A
Where, B is the most basic anionic compound, C is the second most basic anionic compound, A is the least basic anionic compound
Therefore, the order of the anionic compounds from the most basic to least basic is B > C > A. To order the anionic compounds from the most basic to least basic, follow these steps: Identify the anions present in each compound., Determine the conjugate acid of each anion, Compare the strength of the conjugate acids, Order the anionic compounds based on the strength of their conjugate acids (the weaker the conjugate acid, the stronger the base).
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amy combined 10.0 ml of 1.0 m hcl with 5.0 ml of 2.0 m naoh. will the reaction have reached its equivalence point once the reaction is complete?
The reaction has reached its equivalence point once it is complete.
To determine if the reaction has reached its equivalence point once the reaction is complete, we must first calculate the moles of each compound:
HCl moles = 1.0 M x (10.0 mL / 1000 mL/L) = 0.01 mol
NaOH moles = 2.0 M x (5.0 mL / 1000 mL/L) = 0.01 mol
The two compounds react in a 1:1 ratio.
There are now no more moles of HCl or NaOH left to react since they have equal moles.
We can thus conclude that the reaction has reached its equivalence point as soon as the reaction is over. Since the moles of both HCl and NaOH have been completely neutralized, the pH at the equivalence point is 7.
This indicates that the reaction has reached its equivalence point once it has finished.
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observe: use the oxygen gauge to measure the concentration of dissolved oxygen at several different times. how does the oxygen concentration change over a single day?
Answer: The oxygen concentration in water changes over a single day as a result of photosynthesis, respiration, decomposition, and other factors.
The oxygen gauge is used to measure the concentration of dissolved oxygen in water at several different times over a single day. This process is known as dissolved oxygen monitoring.
At the start of the day, the oxygen concentration is typically high due to the photosynthesis of aquatic plants. As the day progresses, the oxygen concentration will drop as a result of respiration by the aquatic organisms in the water. Additionally, sunlight can drive the rate of photosynthesis and respiration, which can cause the oxygen concentration to fluctuate over the course of the day.
By the end of the day, the oxygen concentration is usually lower than it was at the start of the day, as a result of the respiration of aquatic organisms and the decomposition of organic matter. However, in some cases, the oxygen concentration can remain high, due to the photosynthesis of aquatic plants.
It is important to note that the oxygen concentration can also be affected by temperature, light, and other factors. The oxygen concentration can vary depending on the environment, and so it is important to measure the oxygen concentration at different times to get a complete picture of the environment.
Overall, the oxygen concentration in water changes over a single day as a result of photosynthesis, respiration, decomposition, and other factors. Monitoring the oxygen concentration at different times can help us to understand the health of the aquatic ecosystem.
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what is the major product obtained upon addition of br2 to (r)-4-tert-butylcyclohexene? question 6 options: a. (1r,2r,4r)-1,2-dibromo-4-tert-butylcyclohexane b. (1s,2r,4r)-1,2-dibromo-4-tert-butylcyclohexane c. (1s,2s,4r)-1,2-dibromo-4-tert-butylcyclohexane d. (1s,2s,4s)-1,2-dibromo-4-tert-butylcyclohexane
The major product obtained upon addition of Br2 to (R)-4-tert-butylcyclohexene is (1s, 2r, 4r)-1,2-dibromo-4-tert-butylcyclohexane.
The correct option is
b.
(1s,2r,4r)-1,2-dibromo-4-tert-butylcyclohexane.
What is an addition reaction?
An addition reaction occurs when an atom or group of atoms is added to a carbon-carbon double or triple bond to create a single bond. As a result, the double bond vanishes, and the reaction is called an addition reaction.
What is Br2?
Bromine is a halogen element with the symbol Br and the atomic number 35.
Bromine is the only nonmetallic element that is liquid at normal room temperature and pressure, making it one of the few elements that is both a liquid and a halogen. Br2 is the chemical formula for bromine.
Addition of Br2 to (R)-4-tert-butylcyclohexene
When Br2 is added to (R)-4-tert-butylcyclohexene,
the following reaction occurs:
The major product obtained is (1s, 2r, 4r)-1,2-dibromo-4-tert-butylcyclohexane.
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How many torr are in 84.2 mmHg? Round to 1 decimal place and answer in numbers ONLy
When we convert the pressure of 84.2 mmHg to torr, the result obtained is 84.2 torr
How do i convert 84.2 mmHg to torr?The following data were obtained from the question:
Pressure (in mmHg) = 84.2 mmHgPressure (in torr) =?The conversion scale of converting pressure (in mmHg) to pressure (in torr) is given as follow:
760 mmHg = 760 torr
Using the above, scale, we can convert 84.2 mmHg to torr as follow:
760 mmHg = 760 torr
Therefore,
84.2 mmHg = 84.2 torr
From the above calculation, we can conclude that the pressure (in torr) is 84.2 torr
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if 12.23 g of bromomethane are produced when 5.00 g of methanol is reacted with excess hbr, what is the percentage yield?
The percentage yield of bromoethane is 82.45%.
The percentage yield of a reaction can be calculated using the following formula:
Percentage Yield = (Actual Yield / Theoretical Yield) x 100
For this reaction, the theoretical yield of bromomethane is calculated by multiplying the moles of methanol by the moles of bromomethane and its molar mass.
Theoretical Yield = 5.00 g/32.04 g/mol x 1mol x 95g = 14.834 g bromomethane
where 95g is the molar mass of bromomethane.
The actual yield is given as 12.23 g, so the percentage yield is calculated as:
Percentage Yield = (12.23 g/14.834 g) x 100 = 82.45%
Therefore, the percentage yield of bromoethane in the reaction is 82.45%.
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a student needs to prepare a buffer made from and with ph . if ka for is , what ratio of is required?
To prepare a buffer of a desired pH, the Henderson-Hasselbalch equation can be used:
pH = pKa + log([A-]/[HA])
where pH is the desired pH, pKa is the dissociation constant of the weak acid, [A-] is the concentration of the conjugate base, and [HA] is the concentration of the weak acid.
In this case, the weak acid is , and its dissociation reaction is:
↔ +
The dissociation constant (Ka) for this reaction is given as .
To calculate the ratio to required to prepare a buffer at a desired pH, we first need to rearrange the Henderson-Hasselbalch equation as follows:
[A-]/[HA] = 10^(pH - pKa)
Substituting the values, we get:[A-]/[HA] = 10^( - ) =
Therefore, the required ratio of [A-] to [HA] is : . This means that to prepare a buffer at the desired pH, we need to mix of and of in the buffer solution.
What is a Substituting ?Substituting refers to the process of replacing one element, molecule, or group with another in a chemical reaction or a chemical compound. It is a common chemical technique used in various chemical reactions and organic synthesis. By substituting one atom or group for another, it is possible to change the properties and behavior of the molecule or compound, which can have important implications in various fields such as medicine, materials science, and industry.
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Which of the following compounds is the least reactive toward nucleophilic aromatic substitution? A) 1-chloro-4-nitrobenzene B) 1-iodo-2-nitrobenzene C) 1-fluoro-4-nitrobenzene D) 1-bromo-3-nitrobenzene
Benzenesulphonic acids is least sensitive in an electrophilic replacement of an aromatic because of the M effect. 1-Chloro-4-nitrobenzene is the nucleophilic aromatic substitution that is least reactive to it (option A).
By nucleophilic, what do you mean?A substance is referred to as a nucleophile if it has a propensity to give electron pairs to electron acceptors in order to establish chemical bonds with them. Any ion, molecule, or pi bond with two free electrons or an electron pair has the capacity to act in a nucleophilic manner.
A nucleophile, is water?Water attracts electron-deficient compounds like protons, making it a nucleophile. Due to the easy accessibility of a singular electron pair on oxygens, water has a stronger nucleophilic than electrophilic nature.
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To find the percentage yield for a reaction, you take the___ and divide by the___and ___
multiply by____
PLEASE HELP ME
To the percentage yield for a reaction, you take the actual yield and divide by the theoretical yield and multiply by 100.
What is percent yield?Yield also referred to as reaction yield in chemistry, is a measure of the quantity of moles of a product formed in relation to the reactant consumed and expressed as a percentage.
Percent Yield is defined as the actual yield divided by the theoretical yield times 100 i.e.
Percent yield = actual yield/theoretical yield × 100
The percent yield is determined by calculating the ratio of actual yield/theoretical yield.
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