Calculate the pH of a buffer solution made by mixing 300 mL of 0.2 M acetic acid, CH3COOH, and 200 mL of 0.3 M of its salt sodium acetate, CH3COONa, to make 500 mL of solution. Ka for CH3COOH = 1.76×10–5

Answers

Answer 1

Answer:

Approximately [tex]4.75[/tex].

Step-by-step explanation:

Remark: this approach make use of the fact that in the original solution, the concentration of  [tex]\rm CH_3COOH[/tex] and [tex]\rm CH_3COO^{-}[/tex] are equal.

[tex]{\rm CH_3COOH} \rightleftharpoons {\rm CH_3COO^{-}} + {\rm H^{+}}[/tex]

Since [tex]\rm CH_3COONa[/tex] is a salt soluble in water. Once in water, it would readily ionize to give [tex]\rm CH_3COO^{-}[/tex] and [tex]\rm Na^{+}[/tex] ions.

Assume that the [tex]\rm CH_3COOH[/tex] and [tex]\rm CH_3COO^{-}[/tex] ions in this solution did not disintegrate at all. The solution would contain:

[tex]0.3\; \rm L \times 0.2\; \rm mol \cdot L^{-1} = 0.06\; \rm mol[/tex] of [tex]\rm CH_3COOH[/tex], and

[tex]0.06\; \rm mol[/tex] of [tex]\rm CH_3COO^{-}[/tex] from [tex]0.2\; \rm L \times 0.3\; \rm mol \cdot L^{-1} = 0.06\; \rm mol[/tex] of [tex]\rm CH_3COONa[/tex].

Accordingly, the concentration of [tex]\rm CH_3COOH[/tex] and [tex]\rm CH_3COO^{-}[/tex] would be:

[tex]\begin{aligned} & c({\rm CH_3COOH}) \\ &= \frac{n({\rm CH_3COOH})}{V} \\ &= \frac{0.06\; \rm mol}{0.5\; \rm L} = 0.12\; \rm mol \cdot L^{-1} \end{aligned}[/tex].

[tex]\begin{aligned} & c({\rm CH_3COO^{-}}) \\ &= \frac{n({\rm CH_3COO^{-}})}{V} \\ &= \frac{0.06\; \rm mol}{0.5\; \rm L} = 0.12\; \rm mol \cdot L^{-1} \end{aligned}[/tex].

In other words, in this buffer solution, the initial concentration of the weak acid [tex]\rm CH_3COOH[/tex] is the same as that of its conjugate base, [tex]\rm CH_3COO^{-}[/tex].

Hence, once in equilibrium, the [tex]\rm pH[/tex] of this buffer solution would be the same as the [tex]{\rm pK}_{a}[/tex] of [tex]\rm CH_3COOH[/tex].

Calculate the [tex]{\rm pK}_{a}[/tex] of [tex]\rm CH_3COOH[/tex] from its [tex]{\rm K}_{a}[/tex]:

[tex]\begin{aligned} & {\rm pH}(\text{solution}) \\ &= {\rm pK}_{a} \\ &= -\log_{10}({\rm K}_{a}) \\ &= -\log_{10} (1.76 \times 10^{-5}) \\ &\approx 4.75\end{aligned}[/tex].


Related Questions

Which of the following is a like radical to cube rt of 7x

Answers

Answer:

[tex]\sqrt[3]{7x}[/tex]

Step-by-step explanation:

Given

[tex]7x[/tex]

Required

The radical statement

Cube root is represented as:

[tex]\sqrt[3]{}[/tex]

Considering [tex]7x[/tex], the expression is:

[tex]\sqrt[3]{7x}[/tex]

14. 14. If f(x)= sec^2x, thenf'(x)=

Answers

Answer:

1 (2) f(x) = 1 (3) 1< f(x) < 2 (4) f(x) greater than or equal to 2

Step-by-step explanation:

We know AM ≥ GM

(cos2x+sec2x )/2 ≥ √(cos2x sec2x)

(cos2x+sec2x ) ≥ 2√(cos2x (1/cos2x)

f(x) ≥ 2

Hence option (4) is the answer.

We have two circles A and X. The radius and perimeter of the circle A are b and c respectively.
The radius and perimeter of the circle X are y and z respectively. Consider the following ratios
K=c/b and L=Z/y.
Which of the following statements is true? *
K>L
K K=L
K=2L

Answers

Answer:

[tex]K = L[/tex]

Step-by-step explanation:

Given

Circle A

[tex]r = b[/tex] --- radius

[tex]p = c[/tex] ---- perimeter

Circle B

[tex]r = y[/tex] --- radius

[tex]p =z[/tex] --- perimeter

[tex]K = \frac{c}{b}[/tex]

[tex]L = \frac{z}{y}[/tex]

Required

Select the true option

The perimeter of a circle is:

[tex]Perimeter = 2\pi r[/tex] ------ the circumference

So, we have:

[tex]c = 2\pi b[/tex] --- circle A

[tex]z = 2\pi y[/tex] --- circle B

Calculate K

[tex]K = \frac{c}{b}[/tex]

[tex]K = \frac{2\pi b}{b}[/tex]

[tex]K = 2\pi[/tex]

Calculate L

[tex]L = \frac{z}{y}[/tex]

[tex]L = \frac{2\pi y}{y}[/tex]

[tex]L = 2\pi[/tex]

So, we have:

[tex]K = L = 2\pi[/tex]

Frans paid R9600 as interest on a loan he took 5 years ago at 16% rate. What's was the amount he took as loan?

Answers

Step-by-step explanation:

Interest (I)=R9600

Rate(R)=16%

Time (T)=5years

Principal (P)=?

P=100×I÷R×T

P=100×R9600÷16×5

P=R960000÷80

P=R12, 000

Answer:

      The amount he took as loan = R12,000

Step-by-step explanation:

Simple Interest

Let loan amount be = P

R = 16%

T = 5years

I = 9600

Find P

  [tex]I = \frac{PRT}{100}\\\\9600 = \frac{P \times 16 \times 5}{100}\\\\P = \frac{9600 \times 100}{16 \times 5} = 12,000[/tex]

Consider the quadratic function y = 0.3 (x-4)2 - 2.5
Determine the axis of symmetry, x =

Answers

Answer:

[tex]x=4[/tex]

Step-by-step explanation:

We have the quadratic function:

[tex]\displaystyle y=0.3(x-4)^2-2.5[/tex]

And we want to determine its axis of symmetry.

Notice that this is in vertex form:

[tex]y=a(x-h)^2+k[/tex]

Where (h, k) is the vertex of the parabola.

From our function, we can see that h = 4 and k = -2.5. Hence, our vertex is the point (4, -2.5).

The axis of symmetry is equivalent to the x-coordinate of the vertex.

The x-coordinate of the vertex is 4.

Therefore, the axis of symmetry is x = 4.

2.6.58
The lot in the figure shown, except for the house, shed, and driveway, is lawn. One bag of lawn fertilizer
costs $15.00 and covers 3,000 square feet.


Please help :)

Answers

Answer:

50 bags ;

£750

Step-by-step explanation:

The dimension of the rectangular lawn is 500ft by 300 ft

The area of the lawn an e obtained thus :

Area of rectangle = Length * width

Area of rectangle = 500 ft * 300 ft

Area of rectangle = 150000 feets

1 bag of fertilizer covers 3000 feets

The minimum bags of fertilizer required :

Area of rectangle / Area covered by 1 bag of fertilizer

Minimum bags of fertilizer required :

(150,000 / 3000) = 50 bags

50 bags of fertilizer

Cost per bag = 15

Total cost = 15 * 50 = £750

Components arriving at a distributor are checked for defects by two different inspectors (each component is checked by both inspectors). The first inspector detects 83% of all defectives that are present, and the second inspector does likewise. At least one inspector does not detect a defect on 34% of all defective components. What is the probability that the following occur

Answers

Complete question is;

Components arriving at a distributor are checked for defects by two different inspectors (each component is checked by both inspectors). The first inspector detects 83% of all defectives that are present, and the second inspector does likewise. At least one inspector does not detect a defect on 34% of all defective components. What is the probability that the following occurs?

(a) A defective component will be detected only by the first inspector?

b) A defective component will be detected by exactly one of the two inspectors?

(c) All three defective components in a batch escape detection by both inspectors (assuming inspections of different components are independent of one another)?

Answer:

A) 0.17

B) 0.34

C) 0

Step-by-step explanation:

a) We are told that the first inspector(A) detects 83% of all defectives that are present, and the second inspector(B) also does the same.

This means that;

P(A) = P(B) = 83% = 0.83

We are also told that at least one inspector does not detect a defect on 34% of all defective components.

Thus;

P(A' ⋃ B') = 0.34

Also, we now that;

P(A ⋂ B) = 1 - P(A' ⋃ B')

P(A ⋂ B) = 1 - 0.34

P(A ⋂ B) = 0.66

Probability that A defective component will be detected only by the first inspector is;

P(A ⋂ B') = P(A) - P(A ⋂ B)

P(A ⋂ B') = 0.83 - 0.66

P(A ⋂ B') = 0.17

B) probability that a defective component will be detected by exactly one of the two inspectors is given as;

P(A ⋂ B') + P(A' ⋂ B) = P(A) + P(B) - 2P(A ⋂ B)

P(A) + P(B) - 2P(A ⋂ B) ; 0.83 + 0.83 - 2(0.66) = 0.34

C) Probability that All three defective components in a batch escape detection by both inspectors is written as;

P(A' ⋃ B') - (P(A ⋂ B') + P(A' ⋂ B))

Plugging in the relevant values, we have;

0.34 - 0.34 = 0

It takes 5 hr for 2 bricklayers to build a park wall. How long would it take 8 bricklayers to complete the job?

Answers

1 hour and 25 mins
It takes 1 hour and 25 mins to complete the 8 bricklayers job

fill in the blink

Given ,Simplify ,BC=EF ,Multiplication Property of Equality ,Substitution Property of Equality AC=DF DE+EF=DF Reflexive Property of Equality Transitive Property of Equality ,Segment Addition Postulate, Division Property of Equality ,Addition Property of Equality, Distributive Property, Subtraction Property of Equality

Answers

Answer:

see below

Step-by-step explanation:

[tex] \displaystyle AB = DE[/tex]

[given]

[tex] \displaystyle \boxed{BC = EF}[/tex]

[given]

[tex] \displaystyle AB + BC = AC[/tex]

[segment addition Postulate]

[tex] \displaystyle \boxed{DE+ EF=DF}[/tex]

[segment addition Postulate]

[tex] \rm\displaystyle DE+ BC = AC \: \: \text{and} \: \: DE+ BC = DF[/tex]

[Substitution Property of Equality]

[tex] \displaystyle \boxed{AE= DE}[/tex]

[Proven]

I need help nowww!! 16 points

Answers

Answer:

A: x = 0

B: x = All real numbers

Step-by-step explanation:

A.

Any number to the power of (0) equals one. This applies true for the given situation; one is given an expression which is as follows;

[tex](6^2)^x=1[/tex]

Simplifying that will result in;

[tex]36^x=1[/tex]

As stated above, any number to the power of (0) equals (1), thus (x) must equal (0) for this equation to hold true.

[tex]36^0=1\\x=0[/tex]

B.

As stated in part (A), any number to the power (0) equals (1). Therefore, when given the following expression;

[tex](6^0)^x=1[/tex]

One can simplify that;

[tex]1^x=1[/tex]

However, (1) to any degree still equals (1). Thus, (x) can be any value, and the equation will still hold true.

[tex]x=All\ real \ numbers[/tex]

I really need help please

Answers

9514 1404 393

Answer:

  60

Step-by-step explanation:

The minimum number required is the least common multiple (LCM) of 15 and 4. The numbers 15 and 4 have no common factors, so their LCM is their product.

  15×4 = 60 strands are required

In the figure below. JLM is similar to JKN if JM=14 inches what is the length of JN

Answers

Answer:

Hello good evening friend

Which of the following is the value of a when the function (x) - 3|xlis written in the standard form of an absolute value
function?

Answers

Answer:1

Step-by-step explanation:2

2

The value of a when the function f(x) = 3|xl is written in the standard form of an absolute value function is 3.

What is meant by an absolute function ?

An absolute function is defined as a function which consists of an algebraic expression that is within absolute value symbols.

Here,

The standard form of the absolute value function is written by,

f(x) = a|x|

Given that,

f(x) = 3|x|

Comparing this with the standard form, we get,

a|x| = 3|x|

Therefore, a = 3

Hence,

The value of a when the function f(x) = 3|xl is written in the standard form of an absolute value function is 3.

To learn more about absolute function, click:

https://brainly.com/question/14364803

#SPJ7

Lorena and Julio purchased a home for $205,950. Their loan amount was $164,760, and the assessed value is now $200,500. Their tax rate is 1.5%. How much will their monthly taxes be?

Answers

Answer:

Monthly taxes = $250.63 (Approx.)

Step-by-step explanation:

Given:

Amount of purchase = $205,950

Loan amount = $164,760

Assessed value = $200,500

Tax rate is 1.5%

Find:

Monthly taxes

Computation:

Tax always calculated on Assessed value

Annual tax amount = 200,500 x 1.5%

Annual tax amount = 3,007.5

Monthly taxes = Annual tax amount / 12

Monthly taxes = 3,007.5 / 12

Monthly taxes = 250.625

Monthly taxes = $250.63 (Approx.)

Jonathon looked at the picture frame below and computed the following sum 8 3/4 +{-4}. What value did he find

Answers:

x
2y
y
2 x

Answers

Answer:

he found y value

Step-by-step explanation:

y value would be 8 3/4 + (-4) which is equivalent to 8 3/4 - 4 = 4 3/4

What's the lateral area of the following cone?
11 cm
10 cm

511.23 cm
55 cm?
110.02 cm?
189.75 cm?

Answers

Answer:189.75

Step-by-step explanation:

The lateral area of the cone for the height of 11 cm and diameter 10 cm is given by option D. 189.75 cm²

To calculate the lateral area of a cone,  find the curved surface area.

The lateral area of a cone can be calculated using the formula:

Lateral Area = π × r × l

where:

π is the mathematical constant pi (approximately 3.14159)

r is the radius of the base of the cone

l is the slant height of the cone

Height (h) = 11 cm

Diameter (d) = 10 cm

First, we need to find the radius (r) and the slant height (l).

The radius (r) is half of the diameter:

r

= d / 2

= 10 cm / 2

= 5 cm

The slant height (l) can be found using the Pythagorean theorem:

l² = r² + h²

l² = 5² + 11²

l² = 25 + 121

l² = 146

l = √146

 ≈ 12.083 cm

Now, calculate the lateral area:

Lateral Area = π × r × l

Lateral Area = 3.14159 × 5 cm × 12.083 cm

Lateral Area ≈ 189.75 cm²

Therefore, the lateral area of the cone is approximately 189.75 cm². The correct answer is C) 189.75 cm²

learn more about  lateral area here

brainly.com/question/30196078

#SPJ2

A storage box with a square base must have a volume of 80 cubic centimeters. The top and bottom cost $0.20 per square centimeter and the sides cost $0.10 per square centimeter. Find the dimensions that will minimize cost. (Let x represent the length of the sides of the square base and let y represent the height. Round your answers to two decimal places.) x

Answers

Answer:

Box dimensions:

x =  3.42 cm

y = 6.84 cm

C(min) = 14.04 $

Step-by-step explanation:

We need the surface area of the cube:

S(c)  =  2*S₁ ( surface area of top or base) +  4*S₂ ( surface lateral area)

S₁  = x²        2*S₁  = 2*x²

Surface lateral area is:

4*S₂  =  4*x*h                          V(c) =  80 cm³  =  x²*h          h  =  80/x²

4*S₂  = 4*80/x

4*S₂  = 320 / x

Costs

C (x)  =  0.2* 2*x²   +  0.1 * 320/x

Taking derivatives on both sides of the equation we get:

C´(x)  =    0.8*x   -  32/x²

C´(x)  =  0            0.8*x - 32/x²  = 0

0.8*x³  -  32  =  0            x³  =  32/0.8

x³  =  40  

x =  3.42 cm

h =  80/(3.42)²          h  = 6.84 cm

To find out if x = 3.42 brings a minimum value for C we go to the second derivative

C´´(x) =  64/x³       is always positive for  x > 0  

The C(min) = 0.4*(3.42)²  +  32/(3.42)

C(min)  =  4.68 +  9.36

C(min)  = 14.04 $

rotation 180 degrees about the origin.​

Answers

Answer:

Click the rotate 'button' twice.

Observe.

The rotate button is rotating the image about the orgin.

Answer:

Click the rotate 'button' twice.

Observe.

The rotate button is rotating the image about the orgin.

Step-by-step explanation:

If angles A and B are consecutive interior angles, what is the measure of
angle B if angle A measures 75°?
A. 105
B. 75
C. 180°
O
D. 90°
SUBMIT

Answers

Answer:

A

Step-by-step explanation:

180 - 75 = 105

The answer is A
Consecutive interior angles means that they supplementary to each other. Which means they are parallel to each other and also add up to 180

What is the domain of the function f(x) = (-5/6)(3/5)superscript x

Answers

Answer:

[tex]-\infty < x < \infty[/tex]

Step-by-step explanation:

Given

[tex]f(x) = (-\frac{5}{6}) \cdot (\frac{3}{5})^x[/tex]

Required

The domain

There are no undefined points such as denominator of x or square roots.

Hence, the domain is:

[tex]-\infty < x < \infty[/tex]


Algebraically show that each of the given combinations are equivalent to the given functions.
h(x) + j(x) is equivalent to k(x) given:

h(x) = 2x – 3;j(x) = - 4x + 6; k(x) = – 2x + 3

h(x) + j(2) =

Is h(x) + j(x) equivalent to k(x)? yes

Answers

Answer:

YES, they are equal

Step-by-step explanation:

Given the expressions

h(x) = 2x – 3;j(x) = - 4x + 6; k(x) = – 2x + 3

h(x) + j(x) = 2x – 3 + (-4x + 6)

h(x) + j(x) =  2x - 3 -4x + 6

h(x) + j(x) = 2x - 4x -3 + 6

h(x) + j(x) = -2x + 3 = k(x)

This shows that h(x) + j(x) =  k(x)

Find the value of z, the measure of the subtended arc.

86°
47°
188°
94°

Answers

Answer:

188 degrees

Step-by-step explanation:

The measure of the arc is the center angle, that is double of the circumference one

94 * 2 = 188 degrees

HELP HELP HELP MATH⚠️⚠️⚠️⚠️⚠️

Find four consecutive integers with the sum of 2021

Answers

Answer:

This problem has not solution

Step-by-step explanation:

lets the  integers be:

x

x+1

x+2

x+3

so:

x+(x+1)+(x+2)+(x+3)=2021

x+x+x+x+1+2+3=2021

4x+6=2021

4x=2021-6=2015

x=2015/4=503.75

x is not a integer

a bus travel 80 km in 2 hours .find the time in minutes to travel 1000/3 km​

Answers

Answer:

here is your answer

hope this will help for you

Choose the system of inequalities that best matches the graph below.

Answers

Answer:

"D" is the correct answer

Step-by-step explanation:

Drag the label to the correct location on the image

Answers

9514 1404 393

Answer:

  -∞ < y ≤ 12

Step-by-step explanation:

The range is the vertical extent of the graph of the function. Here the function values range from -∞ to a maximum of about 12. An appropriate description is ...

  -∞ < y ≤ 12

Fill in the blank.
The
numbers are {0, 1, 2, 3, 4, ...}.

Answers

Answer:

the answer is 5 and u know the rest

Solve. SHOW ALL YOUR WORK
2.51 * .2

77/ 1.2

Answers

Answer:

0.502

64.1666

Step-by-step explanation:

Detained explanation of the product operation and division operation is attached below.

2.51 * 0.2 = 0.502

(after multiplying) the number of decimal places of the town values is added and counted from the right in the product to place the data Comal point appropriately.

77/1.2 ; values were multiplied by 10 in other to obtain inter values for the denominator.

Please help! Thank you!​

Answers

Answer:

B

Step-by-step explanation:

Divide both sides by 3

Take square root of both sides.

Add 9 to both sides.

The average revenue collected on this flight is $145/seat. However, if the flight is overbooked and the airline needs to rebook a ticketed passenger, United typically gives the customer a free round-trip ticket for a future flight. The cost of this free round-trip ticket averages $330. By how many seats should United overbook for this route

Answers

This question is incomplete, the complete question is;

United Airline flights from Newark to Seattle are typically booked to capacity. However, due to United’s current lenient rebooking policies, on average 17 customers (with a standard deviation of 10) cancel or are no shows for these flights. The average revenue collected on this flight is is $145/seat. However, if the flight is overbooked and the airline needs to rebook a ticketed passenger, United typically gives the customer a free round-trip ticket for a future flight. The cost of this free round-trip ticket averages $330. By how many seats should United overbook for this route?

Answer:

the number of seats that should be overbooked is approximately 12

Step-by-step explanation:

Given the data in the question;

average = 17 customers

standard deviation = 10

Cost of under booking the flight ( underage ); Cu = $145

Cost of overbooking the flight ( Overage ); Co = $330

we calculate the service level

service level = Cu / ( Cu + Co )

we substitute

Service level = 145 / ( 330 + 145 )

= 145 / 475

Service level = 0.3053

In excel, we use NORMSIV function to determine the z-value

z-value = NORMSIV ( 0.3053 )

z -value = -0.509

Now, the number of seats (Q) that should be overbooked will be;

Q = Average cancellations + Z-value × S.D

we substitute

Q = 17 + ( -0.509 × 10 )

Q = 17 + ( -5.09 )

Q = 17 - 5.09

Q = 11.91 ≈ 12

Therefore, the number of seats that should be overbooked is approximately 12

Other Questions
Annenbaum Corporation uses the weighted-average method in its process costing system. This month, the beginning inventory in the first processing department consisted of 2,200 units. The costs and percentage completion of these units in beginning inventory were: Cost Percent Complete Materials costs $ 7,500 65% Conversion costs $ 8,600 45% A total of 10,100 units were started and 7,700 units were transferred to the second processing department during the month. The following costs were incurred in the first processing department during the month: Cost Materials costs $ 127,300 Conversion costs $ 208,800 The ending inventory was 50% complete with respect to materials and 35% complete with respect to conversion costs. What are the equivalent units for conversion costs for the month in the first processing department Please help ASAP!!What tools would you use to find evidence of early human societies in Africa or Asia? List the tools or methods you would use and a description of each. Rewrite in simplest terms: (9x+5)-(-2x+10)(9x+5)(2x+10) . Someone please help me Kelso's has a debt-equity ratio of 0.6 and a tax rate of 35 percent. The cost of equity is 14.5 percent and the after tax cost of debt is 4.8 percent. What is the weighted average cost of capital If x = 7+3 root 5 by 7 - 3 root 5 , find the value of x^2 + 1 by x^2 Sulfonamides:A) interfere with elongation of peptidoglycanB) are metabolic analogs of PABA and block folic acid synthesisC) attach to the 30S ribosomal subunit and disrupt protein synthesisD) damage cell membranesE) block peptidases that cross-link glycan molecules Given a real rate of interest of 3.2%, an expected inflation premium of 5.1%, and risk premiums for investments A and B of 7.4% and 8.9% respectively, find the following: a. The risk-free rate of return, rf b. The required returns for investments A and B Occurs when an area heart muscle dies or is permanently damaged because if an inadequate supply of oxygen to that area; also known as heart attack. Consider random samples of size 1200 from a population with proportion 0.65 . Find the standard error of the distribution of sample proportions. Round your answer for the standard error to three decimal places. Find the Greatest common factor of 120? Show your work! Calculate the number of phosphorus atoms in 6.2g of phosphorus Any help is much appreciated what is the solution for 2y=x+2x-3y=-5 ELECTROLYSIS OF MOLTEN NaCl IS DONE IN A DOWNS CELL OPERATING AT 7.0 VOLTS AND 4.0X10^4A. HOW MUCH Na(s) AND Cl2(g) CAN BE PRODUCED IN 8 HOURS IN SUCH A CELL? Read the following excerpt from a popular work of fiction. As you read, look for clues that tell you which genre the excerpt falls into.What kinds of details help classify this story as science fiction?A. an extraterrestrial or alien raceB. plot events occurring far in the futureC. time traveling into the pastD. scientists as main characters Michelle did a survey in four butterfly parks and wrote the following observations: a construction company built a scale A rectangle has an area of 18 cm2The lengths of the sides are whole numbers.How long could the sides of the rectangle be?Give all the examples you can think of The statement that there must be a preexisting cell in order for a new cell to form is known as cell Chinese immigrants into America saw their move as a A. permanent moveB. a move that was destined for failure. C.a temporary rather than permanent move. D.something that could be casily done.