What is the pH of a CH3NH2 buffer that consists of 0.33 M CH3NH2 and 0.28 M of its conjugate (Kb of CH3NH2 = 3.7x10-4)?

Answers

Answer 1

As a result, the Methylamine buffer solution has a pH of roughly 10.50.

What pH does 0.2 M Methylamine have?

There is a 0.20 M solution. Let represent the methylamine's level of ionisation. Therefore, the solution's pH value is 11.50.

The Henderson-Hasselbalch equation is used to determine a buffer solution's pH:

pH = pKa + log([A-]/[HA])

In this situation, Methylamine is a weak base, while Methylamine is its conjugate. So, using the Kb value of Methylamine, we must calculate the pKa of Methylamine:

Kb = [Methylamine][hydroxide-]/[Methylamine]

pKb = -log(Kb) = -log(3.7x10⁻⁴) = 3.43

pKa + pKb = 14

pKa = 14 - pKb = 14 - 3.43 = 10.57

The Henderson-Hasselbalch equation is now applicable:

pH = pKa + log([A-]/[HA])

pH = 10.57 + log(0.28/0.33)

pH = 10.57 - 0.07

pH = 10.50

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Related Questions

Build the following atoms and provide their name An atom with 3 protons and 4 neutrons: b. An atom with 2 protons and 4 neutrons: An atom with 4 protons and 4 neutrons:​

Answers

Lithium-7 has 3 protons and 4 neutrons, carbon-6 has 2 protons and 4 neutrons, while beryllium-8 has 4 protons and 4 neutrons.

What atom has three protons? three electrons, four neutrons What is the mass number and what is the atomic number of it?

No matter how many neutrons or electrons are present, the nucleus of a lithium atom always has three protons. The atomic number for lithium is always 3, which is evident given that the lithium atom always has three protons. Yet, the mass number in the isotope with 3 neutrons is 6 and in the isotope with 4 neutrons is 7.

What exactly are electrons, neutrons, and protons?

Negatively charged subatomic particles include electrons. A category of subatomic particle having a positive charge is the proton. The strong nuclear force holds the protons together in the atom's nucleus. A subatomic particle with no charge is called a neutron (they are neutral).

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Calculate Osmolarity of 0.50M MgSO4

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The osmolarity of a 0.50 M MgSO4 solution is 1.50 osmol/L.

Como calculate the osmolarity?

To calculate the osmolarity of a solution of magnesium sulfate (MgSO4) with a concentration of 0.50 M, we need to consider the number of particles that contribute to the osmotic pressure in the solution.

MgSO4 dissociates in water to form three ions: one magnesium ion (Mg2+) and two sulfate ions (SO42-).

So, the total number of particles that contribute to the osmotic pressure in the solution is 1 (Mg2+) + 2 (SO42-) = 3.

Therefore, the osmolarity of a 0.50 M MgSO4 solution would be 0.50 M x 3 = 1.50 osmol/L.

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Calculate the volume in millimeters of 0.170 M NaOh that must be added to 379ml 0.0481 3-(N-Morpholino) acid (Mops) to give the solution a ph of 7.55.The pka of MOPS is 7.18

Answers

Therefore, approximately 267.9 mL of 0.170 M NaOH should be added to the 379 mL of 0.0481 M MOPS to obtain a pH of 7.55.

What is the purpose of the Henderson equation?

The following problem illustrates how the Henderson-Hasselbalch equation can be used to determine how much acid and conjugate base should be combined to create a buffer solution with a specific pH.

To calculate the volume of 0.170 M NaOH that must be added to the 379 mL of 0.0481 M MOPS to achieve a pH of 7.55, we can use the Henderson-Hasselbalch equation:

pH = pKa + log([A-]/[HA])

where [A-] is the concentration of the deprotonated form of MOPS and [HA] is the concentration of the protonated form of MOPS.

At pH 7.55, we know that:

7.55 = 7.18 + log([A-]/[HA])

Solving for the ratio [A-]/[HA]:

0.37 = log([A-]/[HA])

2.42 = [A-]/[HA]

Next, we need to determine the concentrations of [A-] and [HA]. At the midpoint of a buffer, the concentrations of [A-] and [HA] are equal, so we can assume that:

[A-] = [HA] = 0.0481 / 2 = 0.02405 M

Now, we can use the equation for the amount of base added to a buffer to find the volume of 0.170 M NaOH required to achieve the desired pH:

Vbase = (Vbuffer × Cbase) / Cacid

where Vbuffer is the volume of the buffer solution, Cbase is the concentration of the NaOH solution, and Cacid is the concentration of the MOPS buffer.

Plugging in the values:

Vbase = (379 mL × 0.170 M) / 0.02405 M

Vbase = 2679 mL or 2.679 L

Converting to milliliters:

Vbase = 2679 mL × 1000 mL/L = 267900 mL or 2.679 L

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How many moles of h2 are needed in produce 3 moles of water

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3 moles of H2 are needed to produce 3 moles of water.

What are moles?

Moles are a unit of measurement that are used to determine how much of a chemical there is. The amount of a material that has the same number of particles (atoms, molecules, ions, etc.) is said to be one mole.

How do you determine it?

In order to create water (H2O), hydrogen gas (H2) and oxygen gas (O2) must react. The balanced chemical equation for this reaction is:

2H2 + O2 -> 2H2O

The stoichiometry of this reaction states that 2 moles of hydrogen gas and 1 mole of oxygen gas combine to form 2 moles of water. Therefore, we require 3/2 * 2 = 3 moles of hydrogen gas in order to make 3 moles of water.

So, 3 moles of H2 are needed to produce 3 moles of water.

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What is the percent composition for C and H in C₂H6?

Answers

Answer:

C- CARBON COMPONENTS ARE IN 2 ATOMS

H- HYDROGEN IS 6

Explanation:

C IS THE ELEMENTIC FORMULAE AND C2 IS THE MOLECULAR FORMULAE.

H IS HYDROGEN AND H6 MOLECULAR FORMULAE

What is the molarity of a solution of phosphoric acid (a tricrotic acid) if 10.00 mL of the phosphoric acid solution requires 38.11 mL of 0.2412 M NaOH solution to titrate it?

Answers

The phosphoric acid solution has a molarity of 0.3067 M.

How can I determine a solution's molarity?

The most common measure for expressing solution concentration is molarity (M), which is calculated by dividing the solute's mass in moles by the volume of the solution in litres: litres of solution/moles of solute equals M.

How is a solution of one molarity made?

The term "molarity" (M) refers to the quantity of solute in moles per litre of solution. A clean 1-L volumetric flask should be halfway filled with distilled or deionized water to create a 1 M solution. Slowly add 1 formula weight of the chemical to the flask. Let the compound to completely dissolve, gently turning the flask as needed.

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A buffer is made by dissolving H3PO4 and NaH2PO4 in water.
Write an equation that shows how this buffer neutralizes added base.

Answers

This reaction can be represented by the following equation: H₃PO₄ + OH⁻ → H₂PO₄⁻ + H₂O

What is buffer solution?

Buffer solution resists the changes in pH when small amounts of acid/ base are added.

In the case of buffer made from H₃PO₄ and NaH₂PO₄, the H₃PO₄ will act as weak acid, and NaH₂PO₄ will act as its conjugate base.

When base is added to this buffer solution, it will react with weak acid (H₃PO₄) to form its conjugate base (H₂PO₄⁻ ) and water (H₂O). The H₂PO₄⁻ ion will then act as weak acid and react with any additional base added to buffer. This reaction can be represented by the following equation: H₃PO₄ + OH⁻  → H₂PO₄⁻  + H₂O

OH⁻  represents any hydroxide ion that may be added to the buffer solution.

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Earth is the only planet in the Solar System with known, sustained life. Which of these things most likely enabled life on Earth to develop? (Choose 3) Responses A Presence of liquid waterPresence of liquid water B Composition of the atmosphereComposition of the atmosphere C Oxygen-rich atmosphereOxygen-rich atmosphere D Size of the Milky Way GalaxySize of the Milky Way Galaxy E Proximity of the Sun

Answers

The three factors A, B, and C are those that most likely allowed life to begin on Earth, Oxygen rich atmosphere.

Why does life only exist on Earth and not on any other planets in the solar system?

A section of the Planet Earth Hall. Why is the Earth a habitable planet. It is at the ideal distance from the Sun, its magnetic field shields it from dangerous solar radiation, and an insulating atmosphere keeps it warm.

What are the three ways the atmosphere affects life on Earth?

It not only protects us from harmful UV solar radiation but also gives us the oxygen we require to survive. Without it, the pressure needed for liquid water to exist on the surface of our planet would not be possible. Also, it warms our globe and maintains livable temperatures.

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HELPPPPP FASTTTT

Gas Stoichiometry: Putting it all together, one step at a time.

Carbon monoxide reacts with nitrogen monoxide to produce nitrogen gas and carbon dioxide. The skeleton equation is CO + NO ---> N2 + CO2. This is the problem: If 42.7 grams of CO is reacted completely at STP, what volume of N2 gas will be produced?

What are the coefficients from left to right in the balanced equation?
options
A. 1,1,1,1
B. 1,1,2,1
C. 2,2,1,2
D. 1,3,1,2
If you start out the reaction with 42.7 grams of CO, how many mol of CO do you have?
OPITIONS
A. 0.97 mol
B. 1.524 mol
C. 1.196 x 10^3 mol
What is the volume of 1 mol of any gas at STP?
options.
A. 2.24 L
B. 22.4 L
C. 24.2 L
D. impossible
What is the last piece of information that you need from the balanced equation to solve for the volume of N2 gas produced?
Options.
A. how many gra,s of CO2 are produced
B. what is the mol ratio CO2 to CO
C. what is the mol ratio of N2 to CO2
D. What is the mol ratio of N2 to CO?
What is the volume of N2 gas produced?
Options
A. 1.50L
B. 17.1 L
C. 51.2 L
D. 64.3L

Answers

The correct answers are: 1,1,1,1; 1.524 mol; 22.4L; the mol ratio of CO to N2 is 1:1; the volume of N2 gas produced is 34.1 L.

How to calculate the volume of a gas?

The balanced chemical equation for the reaction is:

CO + NO ---> N2 + CO2, with coefficients from left to right being 1, 1, 1, and 1. Therefore, the answer is option A.

To calculate the number of moles of CO, we need to divide the given mass by its molar mass. The molar mass of CO is 28.01 g/mol. Thus, the number of moles of CO is 42.7 g / 28.01 g/mol = 1.524 mol.Therefore, the answer is option B.

The volume of 1 mol of any gas at STP (standard temperature and pressure) is 22.4L. Thus, the answer is option B.

To solve for the volume of N2 gas produced, we need to use the coefficients in the balanced equation to determine the mole ratio of CO to N2. The coefficient for CO is 1, and the coefficient for N2 is also 1. Therefore, the mole ratio of CO to N2 is 1:1.

Since 1.524 mol of CO is reacted, an equal number of moles of N2 is produced. Thus, the number of moles of N2 is also 1.524 mol. To convert moles to volume at STP, we can use the volume of 1 mol of any gas at STP (22.4 L). Thus, the volume of N2 gas produced is 1.524 mol × 22.4 L/mol = 34.1 L. Therefore, the answer is not given in the options.

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How many litres of H2 gas (at STP) are needed to Completely
react with 5 moles of
0₂
gas?

Answers

5 moles of Oxygen gas must totally react with 224 litres of Hydrogen gas at STP.

5 moles of Oxygen may make how many moles of Water?

There is nothing in front of this, thus we may place a one. I get three moles of Carbon dioxide and four moles of Water from one mole of this and five moles of Oxygen. According to Avogadro's law, a mole of any gas has a 22.4 L volume at STP.

2Hydrogen(g) + Oxygen (g) → 2Water (g)

From the equation, we can see that 2 moles of Hydrogen are required to react with 1 mole of Oxygen.

Therefore, to react completely with 5 moles of Oxygen, we need:

5 moles Oxygen × 2 moles Hydrogen / 1 mole Oxygen = 10 moles Hydrogen

At STP (standard temperature and pressure), 1 mole of any ideal gas occupies 22.4 L. Therefore, 10 moles of Hydrogen would occupy:

10 moles H2 × 22.4 L/mole = 224 L

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Need answer to #6 of my chemistry homework

Answers

The actual yield of NaCl produced in the reaction is 9.85 g.

What is combination reaction?

A combination reaction is a type of chemical reaction in which two or more substances react to form a single new substance. In other words, the reactants combine or "combine together" to form a product. This type of reaction is also sometimes referred to as a synthesis reaction. Combination reactions often involve the transfer of electrons from one reactant to another, and may involve the breaking and forming of chemical bonds. The general form of a combination reaction can be written as:

A + B → AB

Equation:

The balanced chemical equation for the reaction of sodium (Na) with chlorine (Cl₂) to form sodium chloride (NaCl) is:

2Na + Cl₂ → 2NaCl

To determine the limiting reactant, we need to first calculate the number of moles of each reactant:

Number of moles of Na = 8 g / 23 g/mol = 0.348 moles

Number of moles of Cl₂ = 8 g / 71 g/mol = 0.113 moles

According to the stoichiometry of the balanced equation, 2 moles of Na react with 1 mole of Cl₂ to produce 2 moles of NaCl. Therefore, the number of moles of NaCl that can be produced from the given amounts of reactants is limited by the amount of Cl₂ present.

The theoretical yield of NaCl can be calculated based on the limiting reactant, which in this case is Cl₂:

Moles of NaCl = 0.113 moles Cl₂ x (2 moles NaCl / 1 mole Cl₂) = 0.226 moles NaCl

Mass of NaCl = Moles of NaCl x Molar mass of NaCl

Mass of NaCl = 0.226 moles x 58.44 g/mol = 13.22 g

The actual yield of NaCl is given to be 74.5% of the theoretical yield:

Actual yield = 74.5% x 13.22 g = 9.85 g

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Where is the mistake? Pleaseee I'll give 50 points!

Answers

Answer:

formula

Explanation:

the mistake is in formula please check

actual yeild = 0.493 moles NaCl

mistake

here

How many moles of HNO₃ will be produced from the reaction of 57.0 g of NO₂ with excess water in the following chemical reaction?
3 NO₂(g) + H₂O (l) → 2 HNO₃(g) + NO(g)

Answers

The number of mole of HNO₃ that will be produced from the reaction of 57.0 g of NO₂ with excess water is 0.826 mole

How do i determine the number of mole of HNO₃ produced?

First, we shall obtain the number of mole in 57.0 g of NO₂. This shown below:

Mass of NO₂ = 57 grams Molar mass of NO₂ = 46 g/mol Mole of NO₂ =?

Mole = mass / molar mass

Mole of NO₂ = 57 / 46

Mole of NO₂ = 1.239 mole

Finally, we shall determine the number of mole of HNO₃ produced. Details below:

3NO₂(g) + H₂O(l) → 2HNO₃(g) + NO(g)

From the balanced equation above,

3 moles of NO₂ reacted to produce 2 moles of HNO₃

Therefore,

1.239 mole of NO₂ will react to produce = (1.239 × 2) / 3 = 0.826 mole of HNO₃

Thus, we can conclude that the number of mole of HNO₃ produced is 0.826 mole

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Set up a cell that has a Zn electrode in a 1.0 M aqueous Zn2+ solution on the left side and an Ag electrode in a 1.0 M aqueous Ag+ solution on the right side. Add the salt bridge. What is the balanced net ionic equation for this reaction? Include physical states.

net ionic equation:

Answers

Balanced net ionic equation for this reaction is : Zn(s) + 2Ag⁺(aq) -> Zn²⁺(aq) + 2Ag(s)

What is meant by electrode?

Solid electric conductor that carries electric current into the non-metallic solids, liquids, gases , plasmas or vacuums is called a electrode.

To set up the cell, you will need:

Zn electrode (solid zinc metal) in 1.0 M aqueous Zn⁺ solution on left side

Ag electrode (solid silver metal) in 1.0 M aqueous Ag+ solution on right side

Salt bridge (such as a U-shaped tube filled with a solution of KCl or NaCl)

To set up the cell, connect the Zn electrode to negative (-) terminal of voltmeter and the Ag electrode to positive (+) terminal of voltmeter. Then, connect two electrodes with salt bridge.

Balanced net ionic equation for this reaction is: Zn(s) + 2Ag⁺(aq) -> Zn⁺(aq) + 2Ag(s)

This reaction involves oxidation of zinc (Zn) at Zn electrode, where Zn atoms lose electrons and form Zn⁺ ions: Zn(s) -> Zn²⁺(aq) + 2e⁻

Electrons flow through the external circuit to Ag electrode, where Ag⁺ ions are reduced to solid Ag atoms, gaining electrons: 2Ag⁺(aq) + 2e⁻ -> 2Ag(s)

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Many telescopes have been launched into orbit around Earth or sent out into deep space. What is an advantage of using these telescopes rather than an Earth-bound telescope to gather images?

Question

Telescopes launched into space are usually smaller than ones found on Earth.


The images are usually clearer because they do not have to look through our atmosphere.


It is easier for scientists to make adjustments to an orbiting telescope than a fixed telescope.


Orbiting telescopes usually last longer because it is cold in deep space.

Answers

The advantage of using telescopes launched into orbit around Earth or sent out into deep space is that the images gathered are usually clearer because they do not have to look through our atmosphere.

What is an atmosphere?

The atmosphere can distort and blur images, making it difficult to observe distant objects with high precision. By placing telescopes in space, scientists can avoid this problem and obtain much clearer and more detailed images of objects in the universe. Additionally, space telescopes can observe a wider range of the electromagnetic spectrum, including ultraviolet and infrared radiation, which are absorbed by Earth's atmosphere.

What is telescopes?

A telescope is an instrument used to observe and study distant objects in space by collecting and focusing electromagnetic radiation. Telescopes can be used to study visible light, infrared radiation, ultraviolet radiation, X-rays, and other forms of electromagnetic radiation. They are important tools in astronomy and have helped scientists make many discoveries about the universe. There are many different types of telescopes, including refracting telescopes, reflecting telescopes, and radio telescopes.

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Question is in the picture below, thank you!

Answers

the partial pressure of COCl₂ at equilibrium is 10.25 atm. We are given the following information:

Initial mixture: 45% CO, 55% Cl₂

Total initial pressure: 10.25 atm

Equilibrium reaction: CO(g) + Cl₂(g) ⇌ COCl₂(g)

The equilibrium constant (Kp) = 22.5 (for pressures in atm)

Let's use the following variables to represent the equilibrium concentrations (in atm) of the gases:

[P_CO] = partial pressure of CO

[P_Cl2] = partial pressure of Cl₂

[P_COCl2] = partial pressure of COCl₂

At the start of the reaction, we have:

[P_CO] = 0.45 x 10.25 atm = 4.6125 atm

[P_Cl2] = 0.55 x 10.25 atm = 5.6375 atm

[P_COCl2] = 0 atm (since no COCl₂ is present initially)

At equilibrium, the partial pressures will have adjusted according to the equilibrium constant (Kp) and the stoichiometry of the reaction. Let's assume that x atm of COCl₂ forms at equilibrium. Then, using the stoichiometry of the reaction, we can write:

[P_COCl2] = x atm

[P_CO] = (4.6125 - x) atm

[P_Cl2] = (5.6375 - x) atm

We can now use the equilibrium constant expression to solve for x:

Kp = [P_COCl₂]/([P_CO] x [P_Cl₂])

22.5 = x / ((4.6125 - x) x (5.6375 - x))

22.5 (4.6125 - x) (5.6375 - x) = x

572.71594 - 28.125x + x²= x

x² - 29.125x + 572.71594 = 0

Using the quadratic formula, we get:

x = (29.125 ± sqrt(29.125² - 4 x 1 x 572.71594)) / 2

x = 18.458 atm or 11.667 atm

Since x represents the partial pressure of COCl₂, it cannot be negative, so we must choose the positive root:

x = 18.458 atm

Therefore, at equilibrium, we have:

[P_COCl2] = 18.458 atm

[P_CO] = (4.6125 - 18.458) atm = -13.8455 atm (negative value indicates that no CO is present at equilibrium)

[P_Cl2] = (5.6375 - 18.458) atm = -12.8205 atm (negative value indicates that no Cl₂ is present at equilibrium)

However, negative partial pressures are not physically meaningful. This indicates that our assumption that x atm of COCl₂ forms at equilibrium is incorrect. Instead, all of the CO and Cl₂ must have reacted to form COCl₂. Therefore, at equilibrium:

[P_COCl₂] = [CO] = [Cl₂] = 10.25 - 0 = 10.25 atm

So the partial pressure of COCl₂ at equilibrium is 10.25 atm.

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