Be sure to answer all parts.

Find the pH during the titration of 20.00 mL of 0.1000 M triethylamine, (CH3CH2)3N (Kb = 5.2 × 10−4), with 0.1000 M HCl solution after the following additions of titrant.
20.20 mL:
pH =

Answers

Answer 1

a.

Initial moles of (CH₃CH₂)₃N = (0.1000 mol/L) × (20.00/1000 L) = 0.002 mol

Moles of HCl added = (0.1000 mol/L) × (13.00/1000 L) = 0.0013 mol

Addition of 1 mole of HCl reacts with 1 mole of (CH₃CH₂)₃N to 1 mole of (CH₃CH₂)₃NH⁺.

After addition of 13.00 mL of HCl:

Moles of (CH₃CH₂)₃N left unreacted = (0.002 - 0.0013) mol = 0.0007 mol

Moles of (CH₃CH₂)₃NH⁺ produced = 0.0013 mol

Hence, [(CH₃CH₂)₃NH⁺]/[(CH₃CH₂)₃N] = 0.0013/0.0007 = 13/7

Consider the dissociation of (CH₃CH₂)₃N:

(CH₃CH₂)₃N(aq) + H₂O(l) ⇌ (CH₃CH₂)₃NH⁺(aq) + OH⁻(aq) …… Kb = 5.2 × 10⁻⁴

Henderson-Hasselbalch equation:

pOH = pKb + log([(CH₃CH₂)₃NH⁺]/[(CH₃CH₂)₃N])

pOH = -log(5.2 × 10⁻⁴) + log(13/7) = 3.55

pH = pKw - pOH = 14.00 - 3.55 = 10.45

====

b.

Initial moles of (CH₃CH₂)₃N = 0.002 mol

Moles of HCl added = (0.1000 mol/L) × (20.80/1000 L) = 0.00208 mol

HCl is in excess.

Moles of HCl left unreacted = (0.00208 - 0.002) mol = 0.00008 mol

Volume of the final solution = (20.00 + 20.80) mL = 40.8 mL = 0.0408 L

In the final solution:

[H₃O⁺] = [HCl] = (0.00008 mol) / (0.0408 L) = 0.00196

pH = -log[H₃O⁺] = -log(0.00196) = 2.71

 

====

c.

Initial moles of (CH₃CH₂)₃N = 0.002 mol

Moles of HCl added = (0.1000 mol/L) × (29.00/1000 L) = 0.0029 mol

HCl is in excess.

Moles of HCl left unreacted = (0.0029 - 0.002) mol = 0.0009 mol

Volume of the final solution = (20.00 + 29.00) mL = 49 mL = 0.049 L

In the final solution:

[H₃O⁺] = [HCl] = (0.0009 mol) / (0.049 L) = 0.0184

pH = -log[H₃O⁺] = -log(0.0184) = 1.74


Related Questions

If aqueous solutions of Ba(OH)2 and HNO3 are mixed, what products are formed? Select one: a. BaN2(s) + H2O(l) b. Ba(NO3)2(aq) + H2O(l) c. Ba(s) + H2(g) + NO2(g) d. Ba2O(s) + NO2(g) + H2O(l) e. Ba3N2(s) + H2O(l)

Answers

Answer: Ba(NO3)2(aq) + H2O(l)

Explanation:

The oxidation state for Cl is A. -1 as a reactant and +1 as a product B. -1 as a reactant and 0 as a product C. -1 as a reactant and -1 as a product D. +1 as a reactant and +1 as a product​

Answers

Answer:

no sure

Explanation:

C3H8, + 5O2
+ 5O2,3CO2 + 4H20
If 2.50 moles of C3H8react, how many moles of H20 are produced?

Answers

Answer:

[tex]from \: the \: equation \\ 1 \: moles \: of \: propane \: produce \: 4 \: moles \: of \: water \\ 2.50 \:moles \: of \: propane \: will \: produce \: ( \frac{(2.50 \times 4)}{1} ) \: moles \\ = 10 \: moles \: of \: water[/tex]

One gallon of gasoline (C8H18) weights about 6.3 pounds. Burning gasoline with excess of oxygen forms water and carbon dioxide. When 3.1 gallons of gasoline burn, how many pounds of CO2 emit into the air?

FW: C = 12; H = 1; O = 16.

Answers

Answer:

60 pounds of CO₂ are emited into the air

Explanation:

The combustion of gasoline occurs as follows:

C₈H₁₈(l) + 25/2O₂(g) ⇄ 8CO₂(g) + 9H₂O

Where 1 mole of gasoline produce 8 moles of CO₂

To solve this question we must find the moles of gasoline in 3.1 gallons. 8 times these moles are the moles of CO₂ produced. With the moles of CO₂ we can find its pounds as follows:

Pounds gasoline:

3.1 gallons * (6.3 pounds / gallon) = 19.53 pounds

Grams gasoline:

19.53 pounds * (453.592g / pound) = 8859g

Moles gasoline -Molar mass C8H18: 114.23g/mol-

8859g * (1mol / 114.23g) = 77.55 moles gasoline

Moles CO₂:

77.55 moles gasoline * (8 mol CO₂ / mol Gasoline) = 620.4 moles CO₂

Mass CO₂ - Molar mass: 44.01g/mol-

620.4 moles CO₂ * (44.01g / mol) = 27304g CO₂

Pounds CO₂:

27304g CO₂ * (1lb / 453.592g) =

60 pounds of CO₂ are emited into the air

8. The density of a gas at 350 C is 0,087 g/L. Compute the density at STP.

Answers

Answer:

0.20 g/L

Explanation:

Step 1: Calculate the molar mass of the gas (M)

At T = 350 °C = 623 K and P = 1 atm (we will assume this data), the density (ρ) of the gas is 0.087 g/L. We can calculate the molar mass of the gas using the following expression.

ρ = P × M/R × T

M = ρ × R × T/P

M = 0.087 g/L × (0.0821 atm.L/mol.K) × 623 K/1 atm = 4.5 g/mol

Step 2: Calculate the density of the gas at STP

At standard temperature (T = 273.15 K) and standard pressure (P = 1 atm), the density of the gas is:

ρ = P × M/R × T

ρ = 1 atm × 4.5 g/mol /(0.0821 atm.L/mol.K) × 273.15 K = 0.20 g/L

Is anyone good at chemistry if so can someone help me please ?

(NO LINKS)

Question 15

Answers

We're given the [OH⁻] as 8.34 × 10⁻¹² M. Using the formula pOH = -log[OH⁻], the pOH of this solution would be -log(8.34 × 10⁻¹²) ≈ 11.08.

The pOH is, for lack of a better term, the "opposite" of pH: A pOH of 7 is neutral; a pOH less than 7 is basic; and a pOH greater than 7 is acidic.

This follows from the relation, pH + pOH = 14. In this case, with a pOH of 11.08, our pH would be 14 - 11.08 = 2.92, which is acidic (pH < 7).

Thus, the correct answer choice is B.

Question 3
Which of the objects on the shelf has the greatest inertia?
10 kg
5 kg
2kg
a
b
2 kg
5 kg
10 kg
С
d
The all have the same inertia

Answers

This guy need to stop with this link

Which of these is most likely made of pieces of rock that are weathered by water and wind?

O A diamonds

OB sand

OC grass

OD vegetables​

Answers

Answer:

The answer would be sand.

Explanation:

Sand is weathered down tiny pieces of rock. Sand flows down rivers to shores and slowly builds up to form beaches.

Answer:

The Answer is gonna be B sand

What is the molar mass of AlCl3

Answers

Answer:

133.34 g/moles

Explanation:

but to make life easy it could be 133.4 g/ moles as well

Do not abuse or misuse any piece of drawing instrument. ASAPPPP

Answers

Huhh................



What is the energy of an electron in a Li+ ion when an electron moves from n = 2 to n =3?

Answers

Answer:

The question wants you to determine the energy that the incoming photon must have in order to allow the electron that absorbs it to jump from

n

i

=

2

to

n

f

=

6

.

A good starting point here will be to calculate the energy of the photon emitted when the electron falls from

n

i

=

6

to

n

f

=

2

by using the Rydberg equation.

1

λ

=

R

(

1

n

2

f

1

n

2

i

)

Here

λ

si the wavelength of the emittted photon

R

is the Rydberg constant, equal to

1.097

10

7

m

1

Plug in your values to find

1

λ

=

1.097

10

7

.

m

1

(

1

2

2

1

6

2

)

1

λ

=

2.4378

10

6

.

m

1

This means that you have

λ

=

4.10

10

7

.

m

So, you know that when an electron falls from

n

i

=

6

to

n

f

=

2

, a photon of wavelength

410 nm

is emitted. This implies that in order for the electron to jump from

n

i

=

2

to

n

f

=

6

, it must absorb a photon of the same wavelength.

Worth 100 points plus ill mark brainliest

How many grams of sodium phosphate ( Na₃PO₄ )are required to make 125 milliliters of a 0.240 Molar solution?


4.92

6.48

8.44

12.5

Answers

Answer:

4.92 grams of sodium phosphate (Na₃PO₄) are required to make 125 milliliters of a 0.240 M.

Explanation:

Molarity is a measure of concentration that indicates the number of moles of solute that are dissolved in a given volume.

The molarity of a solution is calculated by dividing the moles of the solute by the volume of the solution:

[tex]Molarity=\frac{number of moles}{volume}[/tex]

Molarity is expressed in units [tex]\frac{moles}{liter}[/tex].

In this case:

Molarity= 0.240 Mnumber of moles= ?volume= 125 mL= 0.125 L

Replacing in the definition of molarity:

[tex]0.240 M=\frac{number of moles}{0.125 L}[/tex]

Solving:

number of moles= 0.240 M*0.125 L

number of moles= 0.03 moles

Being the molar mass of sodium phosphate 164 g/mole, that is, the mass of one mole of the compound, you can calculate the mass of 0.03 moles using the following rule of three: if 1 mole of the compound has 164 grams, 0.03 moles contains how much mass?

[tex]mass=\frac{0.03 moles*164 grams}{1 mole}[/tex]

mass= 4.92 grams

4.92 grams of sodium phosphate (Na₃PO₄) are required to make 125 milliliters of a 0.240 M.

How is water used in society

Answers

Answer:

Water can be used for direct and indirect purposes. Direct purposes include bathing, drinking, and cooking, while examples of indirect purposes are the use of water in processing wood to make paper and in producing steel for automobiles. The bulk of the world's water use is for agriculture, industry, and electricity.

Explanation:

Answer:

water is used for drinking, bathing, cooking, agriculture etc

_FeCI3 + _ NaOH = _ NaCI + _Fe(OH)3 balance and strength the coefficients for each substance

Answers

Answer:

FeCl₃ + 3 NaOH ⇒ 3 NaCl + Fe(OH)₃

Explanation:

Let's consider the following unbalanced equation. This is a double displacement reaction.

FeCl₃ + NaOH ⇒ NaCl + Fe(OH)₃

We will start balancing Cl atoms by multiplying NaCl by 3.

FeCl₃ + NaOH ⇒ 3 NaCl + Fe(OH)₃

Then, we will get the balanced equation by multiplying NaOH by 3.

FeCl₃ + 3 NaOH ⇒ 3 NaCl + Fe(OH)₃

Calculate the number of total atoms in 195 grams of Ni(OH)2.

Answers

1.267 x 10 ^ 24 is the total number of atoms

Please balance the equation C7H16 + CoF3 = C7F16 + HF +CoF2
with solutions

b. how many grams of CH6 is needed to react with 20.0 grams of HF?
C. how many particles of CoF3 is needed to react with 40.0 grams of CzF16?
d. how many grams of CH16 will be produce from 2.03 x 10 molecule of CoFs?
e. Find the Limiting reactant and exXcess reactant in CF16?
6g of CH16
6g of CoFa
f. Find the theoretical yield from CzFi6?
g. What is the percent yield of C;F16 if the actual yield is 1.28 g ?

Answers

haiaoaosoakaoaaonznskepwoa

3.A binary mixture consisting of 50.7 mol % n-butane (1) and the balance iso-butane (2) enters a flash chamber operating at 9.6 bar and 344 K. Use the truncated virial equation of state (equation 3.36 in the textbook) to estimate the composition of the vapor and liquid phases leaving the flash chamber.

Answers

Bdbdbbdbdbdbdbdbdbbdbdbdndndbbdbdbdbbdbdbdbdbd

It takes 53.0 J to raise the temperature of an 11.0 g piece of unknown metal from 13.0∘C to 24.3 ∘C. What is the specific heat for the metal?

Answers

Answer:

Heat absorbed = mS△T

51 = ( 8.2/1000)Kg ×S (11.5)

51×1000= 8.2 (11.5)S

S = 51000/94.3

S = 540.8 J/kg K

10) Is the chemical equation balanced?
2 Al + Fe2O3
2Fe + Al2O3​

Answers

Answer: Yes , the equation is balanced.

Explanation:

According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.

The given chemical equation is:

[tex]2Al+Fe_2O_3\rightarrow 2Fe+Al_2O_3[/tex]

As the number of atoms on reactant side is equal to the number of atoms on product side, the equation is balanced.

Put the steps of the carbon cycle in order using Step 1 as your starting point.

Step 1: Bacteria, through nitrogen fixation and nitrification, convert nitrogen into a usable form.


The animal dies and decomposes, returning nitrogen back to the soil.

Once nitrogen is in usable form, it is taken up by plants and assimilated into proteins..

An animal eats a plant and the nitrogen becomes part of the animal’s proteins.

Answers

Answer:

Carbon moves from the atmosphere to plants. ...

Carbon moves from plants to animals. ...

Carbon moves from plants and animals to soils. ...

Carbon moves from living things to the atmosphere. ...

Carbon moves from fossil fuels to the atmosphere when fuels are burned. ...

Carbon moves from the atmosphere to the oceans.

Explanation:

Answer:

step 4 , 2 , 3

Explanation:

What is the pressure inside a container of 3 moles of gas with a volume of 60 Liters at a temperature of 400 K?


I just need the answer not a link please :)

Answers

1.64 atm

PV = nRT —> P = nRT / V

n = 3 moles
R = 0.08206 L atm / mol K
T = 400 K
V = 60 L

P = (3)(0.08206)(400) / 60 = 1.64 atm

What happens to the solar energy absorbed by plants during photosynthesis ?

Answers

Answer:

Photosynthesis in plants converts solar energy into chemical energy using electrons and protons from water. in plants involves a series of steps and reactions that use solar energy, water, and carbon dioxide to produce organic compounds and oxygen.

Explanation:

Answer:

its is used to make sugar which plants eat think it goes through like glycose or something

Explanation:

A 50.0 mL sample of an aqueous H2SO4 solution is titrated with a 0.375 M NaOH solution. The equivalence point is reached with 62.5 mL of the base. The concentration of H2SO4 is ________ M. A 50.0 mL sample of an aqueous H2SO4 solution is titrated with a 0.375 M NaOH solution. The equivalence point is reached with 62.5 mL of the base. The concentration of H2SO4 is ________ M. 0.150 0.234 0.300 0.469 0.938

Answers

Answer: The concentration of [tex]H_2SO_4[/tex] is 0.234 M

Explanation:

According to the neutralization law,

[tex]n_1M_1V_1=n_2M_2V_2[/tex]

where,

[tex]n_1[/tex] = basicity [tex]H_2SO_4[/tex] = 2

[tex]M_1[/tex] = molarity of [tex]H_2SO_4[/tex] solution = ?

[tex]V_1[/tex] = volume of  [tex]H_2SO_4[/tex] solution = 50.0 ml

[tex]n_2[/tex] = acidity of [tex]NaOH[/tex] = 1

[tex]M_1[/tex] = molarity of [tex]NaOH[/tex] solution = 0.375 M

[tex]V_1[/tex] = volume of  [tex]NaOH[/tex] solution = 62.5 ml

Putting in the values we get:

[tex]2\times M_1\times 50.0=1\times 0.375\times 62.5[/tex]

[tex]M_1=0.234M[/tex]

Therefore concentration of [tex]H_2SO_4[/tex] is 0.234 M

100.00 mL of 0.15 M nitrous acid (HNO2) are titrated with a 0.15 M NaOH solution. (a) Calculate the pH for the initial solution. (b) Calculate the pH for the point at which 80.0 mL of the base has been added. (c) Calculate the pH for the equivalence point. (d) Calculate the pH for the point at which 105 mL of the base has been added.

Answers

Answer:

a. pH = 2.04

b. pH = 3.85

c. pH = 8.06

d. pH = 11.56

Explanation:

The nitrous acid is a weak acid (Ka = 5.6x10⁻⁴) that reacts with NaOH as follows:

HNO₂ + NaOH → NaNO₂(aq) + H₂O(l)

a. At the beginning there is just a solution of 0.12M HNO₂. As Ka is:

Ka = [H⁺] [NO₂⁻] / [HNO₂]

Where [H⁺] and [NO₂⁻] ions comes from the same equilibrium ([H⁺] = [NO₂⁻] = X):

5.6x10⁻⁴ = X² / 0.15M

8.4x10⁻⁵ = X²

X = [H⁺] = 9.165x10⁻³M

As pH = -log [H⁺]

pH = 2.04

b. At this point we have HNO₂ and NaNO₂ (The weak acid and the conjugate base), a buffer. The pH of a buffer is obtained using H-H equation:

pH = pKa + log [NaNO₂] / [HNO₂]

Where pH is the pH of the buffer,

pKa is -log Ka = 3.25

And [NaNO₂] [HNO₂] could be taken as the moles of each compound.

The initial moles of HNO₂ are:

0.100L * (0.15mol / L) = 0.015moles

The moles of base added are:

0.0800L * (0.15mol / L) = 0.012moles

The moles of base added = Moles of NaNO₂ produced = 0.012moles.

And the moles of HNO₂ that remains are:

0.015moles - 0.012moles = 0.003moles

Replacing in H-H equation:

pH = 3.25 + log [0.012moles] / [0.003moles]

pH = 3.85

c. At equivalence point all HNO2 reacts producing NaNO₂. The volume added of NaOH must be 100mL. That means the concentration of the NaNO₂ is:

0.15M / 2 = 0.075M

The NaNO₂ is in equilibrium with water as follows:

NaNO₂(aq) + H₂O(l) ⇄ HNO₂(aq) + OH⁻(aq) + Na⁺

The equilibrium constant, kb, is:

Kb = Kw/Ka = 1x10⁻¹⁴ / 5.6x10⁻⁴ = 1.79x10⁻¹¹ = [OH⁻] [HNO₂] / [NaNO₂]

Where [OH⁻] = [HNO₂] = x

[NaNO₂] = 0.075M

1.79x10⁻¹¹ = [X] [X] / [0.075M]

1.34x10⁻¹² = X²

X = 1.16x10⁻⁶M = [OH⁻]

pOH = -log [OH-] = 5.94

pH = 14-pOH

pH = 8.06

d. At this point, 5mL of NaOH are added in excess, the moles are:

5mL = 5x10⁻³L * (0.15mol / L) =7.5x10⁻⁴moles NaOH

In 100mL + 105mL = 205mL = 0.205L. [NaOH] = 7.5x10⁻⁴moles NaOH / 0.205L =

3.66x10⁻³M = [OH⁻]

pOH = 2.44

pH = 14 - pOH

pH = 11.56

g Consider (12.5 A) micro-grams of a radioactive isotope with a mass number of (78 B) and a half-life of (32.6 C) million years. If energy released in each decay is 32.6 keV, determine the total energy released in joules (J) in 1 (one) year. Give your answer with three significant figures.

Answers

Answer:

Energy released =  18.985 J

Explanation:

The  exponential decay of radioactive substance is given by -

N(t) = N₀ [tex]e^{-kt}[/tex]

where

N₀ = initial quantity

k = decay constant

Half life, [tex]t_{1/2} = \frac{ln 2}{k}[/tex]

⇒[tex]k = \frac{ln 2}{t_{1/2} }[/tex]

Given,

N₀ = 12.5 + 3 = 15.5 × 10⁻⁶ gm

[tex]t_{1/2}[/tex] = 32.6 + 18 = 50.6 × 10⁶ years

So,

[tex]k = \frac{ln 2}{50.6 * 10^{6} }[/tex] = 1.361 × 10⁻⁸ year⁻¹

Now,

N(1) = 15.5 × 10⁻⁶  [tex]e^{-1.361*10^{-8} *1}[/tex]

      = 15.49999978904

Now,

Substance decayed = N₀ - N(t)

                                 = 15.5 × 10⁻⁶ - 15.49999978904 × 10⁻⁶

                                 = 21.095 × 10⁻¹⁷ kg

⇒Δm = 21.095 × 10⁻¹⁷ kg

So,

Energy released = Δmc²

                           = 21.095 × 10⁻¹⁷ × 3 ×10⁸ × 3 × 10⁸

                          = 189.855 ×10⁻¹

                          = 18.985 J

⇒Energy released =  18.985 J

Help hurry please !!!!!

Answers

I think it’s c (sorry if you got it wrong but it makes the most sense to me)

Balance the single replacement chemical reaction.

Answers

Explanation:

B) 3CuCl2+2AL..….2AlCl3+3Cu

hope it helps.

Balanced Equation:

3CuCl₂ + 2Al = 2AlCl₃ + 3Cu


What is the molarity (M) of a solution that has 0.50 moles of solute dissolved in 1.0
liter of solution?

Answers

Answer:

it is 0.50=0.5 M

Explanation:

Molarity definition is measure the concentration of solution.

and the rule is

molarity(M)= moles of solute/volume of solution in liters

Ex: 2.1 M MgCl2= 2.1 mole MgCl2/ L MgCl2 solution

Which of the following astronomical bodies would most likely be the largest?
1. A dwarf star from a nearby solar system
2. A comet
3. One of the gas giants in our solar system
4. Ganymede, the largest moon of Jupiter

Answers

Answer:

1

because a dwarf star will seemlarge because of the in ability of any human being to see d sun

Calculate the enthalpy change for the photosynthesis of gluclose

Answers

Answer:

jhdgafhgafhagfhafg

Explanation:

Other Questions
Please help, no spam! What kinds of things did Maya do at night school in I Know Why The Caged Bird Sings? which equation can be used to solve for x in the diagram? a- 11x = 7xb- 7x + 90 = 11xc- 7x + 11z = 180d- 7x + 11x = 90 I was willing to carry the argument (more far, further) than he was,We raised far more mucher) money this year than last. 45. Which of the following is not considered an eating disorder by NEDIC? (5 points)anorexiaO binge eatingO caloric reductionbulimia You go to the quad on a windy day to fly a kite. You have released 40 feet of string. The string makes an angle of 36 with the ground. How high is the kite in the air? Round your answer to the nearest tenth. Show your work!. what is -5 plus s/5 Les than of equal to 7? HELP ME PLEASE!!!!!!!!!! Please help Ill mark brainliest Which situation results in a final value of zero If you could explain to me how you get the answer, that will be great! What does making an inference mean?a.guessing the answersc.making educated assumptions about meaningb.knowing the answerd.none of the aboveHELP 2. Use the distributive property to write an expression that is equivalent to 12 + 4x. Please Help!!!! Due today will give brainliest If one loaf of bread requires 450g of flour determine the maximum number of loaves of bread that can be baked from 12,5kg of flour What type of invertebrate are robber crabs This Question: 1 pt20 of 20This QuthThe pH of a fruit juice is 2.9. Find the hydronium ion concentration, [H30 * ), of the juice. Use the formula pH = -log[H30*]The hydronium ion concentration [H30 + ] is approximately moles per liter.(Use scientific notation. Use the multiplication symbol in the math palette as needed. Round to the nearest tenth as needed.) A worldwide organization of academics claims that the mean IQ score of its members is 118, with a standard deviation of 17. A randomly selected group of 40 members of this organization is tested, and the results reveal that the mean IQ score in this sample is 115.8. If the organization's claim is correct, what is the probability of having a sample mean of 115.8 or less for a random sample of this size Please help me answer these two questions. Thanks When riding your bike on a main road you should always follow the rules of the _________.roadbikers guidewalkerstown they are riding in For a cheese-lover, Burger King's Mac n' Cheetos are what type of product? (1pt)