can someone help me with part b of question please.

Can Someone Help Me With Part B Of Question Please.

Answers

Answer 1
Answer

125

Explanation

5 • 10^6 = 5,000,000

4 • 10^4 = 40,000

5,000,000 / 40,000 = 125
Answer 2

Answer:

125

Step-by-step explanation:

They want you to work out  \(\\\frac{5 *10^{6} }{4*10^{4} }\)

5 x 1000000/ 4 x 10000

\(\frac{5000000}{40000}\) = 125

Please let me know if it's not correct.

Hope this helps :)


Related Questions

The side of a right triangle opposite the right angle.

Answers

Answer:

hypotenuse

Step-by-step explanation:

The side opposite the right angle has a special name - hypotenuse

The other two sides of the right triangle are called legs

Please help me with my question I’ll give brainliest if correct

Please help me with my question Ill give brainliest if correct

Answers

Answer:

Therefore, the maximum height reached by the rocket is approximately 2080 feet.

Step-by-step explanation:

The given equation is y = -16x² + 400x + 80.

This is a quadratic function with a negative coefficient of x², which means that it is a downward facing parabola. The maximum point of this parabola represents the highest point reached by the rocket.

The x-coordinate of the vertex of the parabola can be found using the formula x = -b/2a, where a = -16 and b = 400.

x = -400/(2*(-16)) = 12.5

So the maximum height is reached 12.5 seconds after launch.

To find the corresponding y-coordinate, we substitute x = 12.5 into the equation:

y = -16(12.5)² + 400(12.5) + 80 = 2080

Answer:  550 ft

Step-by-step explanation:

the equation they gave is a quadratic/parabola.  To find the max you  will need to find the vertex because the max/min of a parabola is the vertex

y is your height

x is your time in sec

y = -16x² + 160x +150

To find vertex use \(x = -\frac{b}{2a}\)

a = -16

b = 160

c = 150

\(x = -\frac{160}{2(-16)}\)

x = 5      This is the time that it happens 5 sec

Plug back in to find max/vertex height

y = -16x² + 160x +150

y = -16(5)² + 160(5) +150

y=550

Max height is at 550 ft

The radius of a circle is 1 inch. What is the circle's area? r=1 in Use 3.14 for ​.

Answers

Answer:

3.14

Step-by-step explanation:

area=pi times the square of radius

1^2 = 1 x 3.14=3.14


What is the y-intercept of y=-4/3x+4?
A) (0,4)
B) (4,0)
C) (0.-4)
D) (-4,0)



PLEASE HELP ME

Answers

Answer:

A. (0,4)

Step-by-step explanation:

You can calculate the y intercept when x = 0.

Substitute 0 for x:

y = (-4/3)(0) + 4

= 0 + 4

= 4

A carton of grapefruit juice displays the nutritional information shown below. How many grams of sugar are there in a 200 ml glass of juice? Grapefruit juice 250 ml contains Carbohydrate Sugar Protein 19.5 g | 16.5 g | 1.5 g​

A carton of grapefruit juice displays the nutritional information shown below. How many grams of sugar

Answers

Answer:

13.2 g

Step-by-step explanation:

let x = grams sugar in a 200 ml glass

16.5 g sugar / 250 ml = x g sugar / 200 ml

x(250) = (16.5)(200)

x =  (16.5)(200) / (250) = 3300 / 250 = 13.2

Answer:  there are 13.2 g sugar in a 200 ml glass of juice

Write and solve a proportion to answer the question.

75% of 124 is what number a
?














Write and solve a proportion to answer the question.

72 is what percent of 45?

Answers

75 percent *124 =

(75:100)*124 =

(75*124):100 =

9300:100 = 93



72÷45×100
= 160

The number of a two dollar bill i need to pay for a purchase is 9 more than the number of 5 dollar bills i need to pay for the same purchase what is the cost of the purchase?

Answers

Answer:

$60

Step-by-step explanation:

Let's say we need t $2 bills and v $5 bills.

We need 9 more $2 bills than $5 bills, so:

t = 9 + v

We also know that the amount of money in t $2 bills is 2 * t = 2t. The amount of money in v + 9 $5 bills is 5 * (v + 9) = 5v + 45. These amounts are equal:

5v + 45 = 2t

Plug v + 9 in for t in 5v = 2t + 18:

5v = 2t + 18

5v = 2 * (9 + v) + 18

5v = 18 + 2v + 18

3v = 36

v = 12

We have 12 $5 bills, so that total cost is 12 * 5 = $60.

~ an aesthetics lover

Reading through a credit card disclosure (aka the Schumer Box), you see the APR for a specific card is set at 9.99% - 23.99%. Which statement is true?

Answers

One of the primary factors determining your card's A.P.R. is your credit score is "True". The correct answer is B.

Credit card issuers evaluate applicants' creditworthiness based on their credit scores, among other factors, and use this information to determine the interest rate they will be charged. Higher credit scores generally result in lower A.P.R.s, reflecting a lower risk profile.

However, it is important to note that the specific A.P.R. offered to an individual may also depend on other factors, such as the card's terms and conditions, the applicant's income, and the card issuer's policies. It is incorrect to assume that most cardholders pay the lowest rate listed when given a range of A.P.R.s, as individual circumstances and creditworthiness vary.

Additionally, higher A.P.R.s do not benefit cardholders, as they result in increased interest charges. The notion that A.P.R.s on credit cards are usually fixed and not adjusted is also incorrect, as A.P.R.s can be variable and subject to change based on various factors.

Therefore, the correct answer is B) One of the primary factors determining your card's A.P.R. is your credit score.

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Note: The question would be as

Reading through a credit card disclosure (aka the Schumer Box), you see the A.P.R. for a specific card is set at 9.99% -23.99%. Which of the following statements is probably TRUE?

a. When given a range of A.PR.s like this, you can assume most cardholders pay the lowest rate listed

b. One of the primary factors determining your card's A.P.R. is your credit score

c. With credit card A.PR.s, cardholders like higher A.P.R.s because they earn more

d. The A.PR. on credit cards is usually fixed so they won't be adjusted as long as you are a cardholder

Need help ASAP !!please

Need help ASAP !!please

Answers

Answer:

:)

Step-by-step explanation:

The point of vertical curvature (PVC) on a road is the point where a vertical curve begins. A highway engineer determined that the elevation of a road on a crest curve x feet after its PVC is modeled by the function f(x)=−0.00002x^2+0.05x+1600. What is the average rate of change between the PVC (x = 0) and the point 1000 ft after the PVC? ft/ft

Answers

The average rate of change between the PVC (x=0) and point 1000 is 0.03.

What is average?

The average of a function is defined as the sum of all the terms that are present in the function divided by the total number of terms in the function.

Here the function is \(f(x)=-0.00002x^{2} +0.05x+1600\)

To find the rate of the function differentiate it with respect to x

\(f('x)=-0.00004x+0.05\)

Now put the value x = 0

\(f('0)=0.05 (i\)

Now, put x = 1000

\(f('1000)=-0.04+0.05=0.01 (ii\)

Now, the average of the PVC at x= 0 and the x=1000

Average is \(\frac{0.05+0.01}{2}\\ \frac{0.06}{2}=0.03\)

Hence, the average rate change is 0.03.

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which of the following is closest to the probability that the total weight of three randomly selected grapefruits is more than 3.4 pounds? A. 0.0274 B. 0.1335 C. 0.2611 D. Nearly 0 E. 0.2514

Answers

The probability of Z being greater than 4 is nearly 0 (option D). Therefore, the answer is D.

Let's assume that the weight of a grapefruit follows a normal distribution with mean 0.9 pounds and standard deviation 0.1 pounds. Then, the weight of three grapefruits will follow a normal distribution with mean 2.7 pounds (3 x 0.9) and standard deviation 0.1732 pounds (sqrt(3) x 0.1).

Now, we need to find the probability that the total weight of three grapefruits is more than 3.4 pounds. We can standardize the distribution by subtracting the mean from 3.4 and dividing by the standard deviation:

Z = (3.4 - 2.7) / 0.1732 = 4

Using a standard normal distribution table or calculator, we can find that the probability of Z being greater than 4 is nearly 0 (option D). Therefore, the answer is D.

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I will mark as brainiest!!!! Plzzzz help

I will mark as brainiest!!!! Plzzzz help

Answers

Answer:

A) One hundred random students

Step-by-step explanation:

I need help with these please not number 3

I need help with these please not number 3

Answers

Answer: A)  -4.6

b) 4.6 spaces left from the original spot

c) the totaal distance travled was 18.2 cm

Step-by-step explanation:

for a you add the amounts together, if you go left that's negative so you use subtraction

for b you count the amount you have from zero

for c you add all the numbers together and forget the signs

A forest fire which is initially 60 acres grows by 20% each day. firefighters battling the blaze can put out 15 acres of fire per day. what is the recursive rule for the number of an acres at the beginning of the nth day. how many acres are burning at the 8th day?

Answers


The recursive rule for the number of acres at the beginning of the nth day in a forest fire that grows by 20% each day and is battled by firefighters who can put out 15 acres per day is given by: A(n) = 1.2 * A(n-1) - 15, where A(n) represents the number of acres at the beginning of the nth day. Using this rule, we can calculate that there are 89.6 acres burning at the beginning of the 8th day.

Explanation: To determine the recursive rule for the number of acres at the beginning of the nth day, we need to consider the given information. The forest fire initially covers 60 acres and grows by 20% each day. This means that the number of acres at the beginning of the next day (n+1) is 1.2 times the number of acres at the beginning of the current day (n). However, the firefighters are able to put out 15 acres of fire per day.

Therefore, to calculate A(n), we start with the initial number of acres, which is 60, and apply the recursive rule. A(n) = 1.2 * A(n-1) - 15. This formula takes into account the growth of the fire by 20% and the reduction of 15 acres due to the firefighters' efforts. By substituting the values, we can calculate the number of acres at the beginning of each day.

To find the number of acres burning at the 8th day, we substitute n = 8 into the recursive rule. A(8) = 1.2 * A(7) - 15. We need to determine A(7) first by substituting n = 7, and so on, until we reach the initial value A(1) = 60. Once we have calculated A(8), we can determine that there are 89.6 acres burning at the beginning of the 8th day

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Which of the following points are located 3 units from (-4,-2) ?

Answers

the units (-3,-1) and (-0,-0) are the following units located at (-4,-2).

A common experiment in organic chemistry labs involvs the dehydration of cyclohexanol (an alcohol) to form cyclohexene. Would infrared spectroscopy help determine if your reaction was successful

Answers

Yes, infrared spectroscopy would indeed be helpful in determining,

if the dehydration reaction of cyclohexanol to form cyclohexene was successful in an organic chemistry lab.

Infrared spectroscopy (IR spectroscopy) is a widely used analytical technique in organic chemistry,

That provides information about the functional groups present in a compound.

It measures the absorption of infrared radiation by the sample,

Which corresponds to the vibrations of different chemical bonds in the molecule.

In the case of cyclohexanol and cyclohexene, there is a significant difference in their functional groups.

Cyclohexanol contains an -OH group alcohol, whereas cyclohexene contains a carbon-carbon double bond alkene.

These functional groups have characteristic absorption bands in the IR spectrum.

By comparing the IR spectra of the starting material cyclohexanol and the desired product cyclohexene.

One can determine if the dehydration reaction was successful.

The presence or absence of characteristic absorption bands for the alcohol (-OH) and the alkene (C=C).

In the product spectrum can provide evidence of the reaction's success.

If the desired cyclohexene is formed, the absorption band corresponding to the -OH group should disappear,

Indicating the removal of the alcohol functionality.

Additionally, a new absorption band corresponding to the C=C bond should appear in the product spectrum.

Therefore, IR spectroscopy can be a valuable tool in confirming the success of the dehydration reaction and characterizing the functional groups present in the resulting product.

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How are the areas of triangles and parallelograms in the coordinate
plane calculated?

Answers

Answer:

___________________________________________________________

By finding the product of a point's x coordinate times the next point's y coordinate, then subtracting the y coordinate of the first point times the x coordinate of the second coordinate and dividing by two, you will find the area of the polygon.

___________________________________________________________

This is the 3rd time I'm posting this with no response. The last time someone commented something completely unrelated to the topic so please no one do that again but I really need help with this. I'd really appreciate it. Thanks!

This is the 3rd time I'm posting this with no response. The last time someone commented something completely
This is the 3rd time I'm posting this with no response. The last time someone commented something completely

Answers

Answer:

20 pts

Step-by-step explanation:

A marching band wants to raise $20,000 at its annual fundraiser. If they sell tickets for $20 a piece, how many tickets will they have to sell ?

Answers

Answer:

1000

Step-by-step explanation:

20,000 divided by 20 is 1,000!

Do the points lie on the line of the given equation. Y = -0.25 X. Show your work.
(4, 1)
(-8, 2)
(6, -1.5)

Answers

Yes all the points lay in the line.
Insert the x coordinate into x giving you your y

Write two fractions with different denominators whose LCD (lowest common denominator) is 36.

Answers

Answer:

2/9 and 3/12

Step-by-step explanation:

2/9 = 8/36

3/12 = 9/36

Consider circle Y with radius 3 m and central angle XYZ measuring 70°.

Circle Y is shown. Line segments Y Z and Y X are radii with lengths of 3 meters. Angle Z Y X is 70 degrees.

What is the approximate length of minor arc XZ? Round to the nearest tenth of a meter.

1.8 meters
3.7 meters
15.2 meters
18.8 meters

Answers

Answer:

3.7

Step-by-step explanation:

The lenght of an arc with a radius of 3m and substended angle of 70 degrees is 3.7meters

How to calculate the length of an arc

The length of an arc is expressed as:

L = r theta

Given the following parameters

r = 3m

theta = 70 degrees = 70π/180

L = 3(70π/180)

L = 3.7 metres

Hence the lenght of an arc is 3.7meters

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Angelo's Restaurant received their delivery of supplies on Monday. The table shows what they ordered
Complete the table to find the total weight of each item delivered

Angelo's Restaurant received their delivery of supplies on Monday. The table shows what they orderedComplete

Answers

Ground Beef - 480
Sugar - 260
Bananas - 288
Pasta - 396
You just multiply the packs and the pounds.

Find the order of every element of (Z18, +).

Answers

The order of every element in (Z18, +) is as follows:

Order 1: 0

Order 3: 6, 12

Order 6: 3, 9, 15

Order 9: 2, 4, 8, 10, 14, 16

Order 18: 1, 5, 7, 11, 13, 17

The set (Z18, +) represents the additive group of integers modulo 18. In this group, the order of an element refers to the smallest positive integer n such that n times the element yields the identity element (0). Let's find the order of every element in (Z18, +):

Element 0: The identity element in any group has an order of 1 since multiplying it by any integer will result in the identity itself. Thus, the order of 0 is 1.

Elements 1, 5, 7, 11, 13, 17: These elements have an order of 18 since multiplying them by any integer from 1 to 18 will eventually yield 0. For example, 1 * 18 ≡ 0 (mod 18).

Elements 2, 4, 8, 10, 14, 16: These elements have an order of 9. We can see that multiplying them by 9 will yield 0. For example, 2 * 9 ≡ 0 (mod 18).

Elements 3, 9, 15: These elements have an order of 6. Multiplying them by 6 will yield 0. For example, 3 * 6 ≡ 0 (mod 18).

Elements 6, 12: These elements have an order of 3. Multiplying them by 3 will yield 0. For example, 6 * 3 ≡ 0 (mod 18).

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can someone please help with this

can someone please help with this

Answers

All correct proportions include the following:

A. \(\frac{AC}{CE} =\frac{BD}{DF}\)

D. \(\frac{CE}{DF} =\frac{AE}{BF}\)

What are the properties of similar geometric figures?

In Mathematics and Geometry, two geometric figures are said to be similar when the ratio of their corresponding side lengths are equal and their corresponding angles are congruent.

Hence, the lengths of the pairs of corresponding sides or corresponding side lengths are proportional to one another when two (2) geometric figures are similar.

Since line segment AB is parallel to line segment CD and parallel to line segment EF, we can logically deduce that they are congruent because they can undergo rigid motions. Therefore, we have the following proportional side lengths;

\(\frac{AC}{CE} =\frac{BD}{DF}\)

\(\frac{CE}{DF} =\frac{AE}{BF}\)

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Planet A has a mass of 5*10^26 kilograms. Planet B has a mass of 2*10^28 kilograms. Choose which planet has the larger mass. Then fill in the blank with a number written in standard notation.

Answers

The planet that has the larger mass is the planet B and the measurements in standard forms are

Planet A = 500000000000000000000000000 kilograms Planet B = 20000000000000000000000000000 kilograms

How to determine the planet that has the larger mass

From the question, we have the following parameters that can be used in our computation:

Planet A = 5*10^26 kilograms

Planet B = 2*10^28 kilograms

Rewrite the masses properly

So, we have

Planet A = 5*10²⁶ kilograms

Planet B = 2*10²⁸ kilograms

The exponent 28 is greater than the exponent 26

This means that

2*10²⁸ is greater than 5*10²⁶

So, we have

Planet B has the larger mass

When the measurements are expressed in standard forms, we have

Planet A = 500000000000000000000000000 kilograms

Planet B = 20000000000000000000000000000 kilograms

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A pole that is 3.1 m tall casts a shadow that is 1.1 m long. At the same time, a nearby building casts a shadow that is 37.25 m long. How tall is the building?Round your answer to the nearest meter.х5?

Answers

Let's determine the height of the building using ratios and proportions.

\(\text{ }\frac{\text{ Height of Pole}}{\text{ Shadow length of Pole}}\text{ = }\frac{\text{ Height of Building}}{\text{ Shadow length of Building}}\)\(\text{ }\frac{\text{ 3.1}}{\text{ 1.1}}\text{ = }\frac{\text{ h}}{\text{ 37.25}}\)

Where,

h = height of the building

We get,

\(\text{ }\frac{\text{ 3.1}}{\text{ 1.1}}\text{ = }\frac{\text{ h}}{\text{ 37.25}}\)\(\text{ 3.1 x 37.25 = h x 1.1}\)

\(115.475=1.1h\)

\(\frac{115.475}{1.1}=\frac{1.1h}{1.1}\)

\(\begin{gathered} \text{ 104.97727272727 = h} \\ \text{ h = 104.97727272727} \end{gathered}\)

\(\text{ h }\approx\text{ 105 m}\)

Therefore, the height of the building is approximately 105 m.

what is a measure of an angle between the perpendicular
bisectors of two adjacent sides of a regular polygon 3
Sides ?​

Answers

Answer:

2/5*180=72

360/72=5

as simple as that you just need to read on polygons

Step-by-step explanation:

pls give me brainlyist

Admission to a local aquarium is $10 for
adults and $7 for children. The aquarium
collected $6,549 from the sale of 783
tickets. Find the number of adult tickets and
children tickets that were sold.

Answers

First, let's define variables:

A = adults

C = children

Okay, now that's done, time to set up the two equations required to solve:

10a + 7c = 6549

a + c = 783

One way you can solve this is to set up the second equation to isolate a variable. For example,

a = -c + 783

Using this, we can plug it into the first equation and solve for c.

10(-c+783) + 7c = 6549

-3c = -1281

c = 427

Now, use the value of 427and plug it in either equation to solve for a.

a + 427 = 783

a = 356

356 adult tickets were sold, and 427 children tickets were sold.

suppose that f ( x , y ) = √ 2 2 − x 2 − y 2 at which { ( x , y ) ∣ x 2 y 2 ≤ 2 2 } . The critical point of f(x,y) restricted to the boundary of D, not at a corner point, is at (a,b). Then a=____
and b=___
Absolute minimum of f(x,y) is ___
and absolute maximum is ___

Answers

The value for a = -2 and b = 0, the absolute minimum of f(x, y) is 0, and the absolute maximum is 2.

What is function?

In mathematics, a function is a unique arrangement of the inputs (also referred to as the domain) and their outputs (sometimes referred to as the codomain), where each input has exactly one output and the output can be linked to its input.

To find the critical points of the function f(x, y) = √(2² - x² - y²) restricted to the boundary of D, we need to consider the condition x² + y² = 2².

Let's solve for x² + y² = 2² and substitute it into the function f(x, y):

x² + y² = 2²

Simplifying, we have:

x² + y² = 4

Substituting this into f(x, y), we get:

f(x, y) = √(2² - x² - y²) = √(4 - x² - y²)

To find the critical points, we need to find where the partial derivatives of f(x, y) equal zero. Since we are restricted to the boundary of D, we can use Lagrange multipliers to consider the constraint x² + y² = 4.

Let's set up the Lagrange multiplier equation:

∇f(x, y) = λ∇g(x, y)

where g(x, y) = x² + y² - 4 and ∇ denotes the gradient.

Calculating the gradients:

∇f(x, y) = <-x/√(4 - x² - y²), -y/√(4 - x² - y²)>

∇g(x, y) = <2x, 2y>

Setting the components equal, we have:

-x/√(4 - x² - y²) = 2xλ

-y/√(4 - x² - y²) = 2yλ

x² + y² = 4

We can simplify the equations by canceling out the x and y terms (assuming they are not zero):

1/√(4 - x² - y²) = 2λ

x² + y² = 4

From the second equation, we know that x² + y² = 4. Substituting this into the first equation, we get:

1/√(4 - 4) = 2λ

1/√0 = 2λ

0 = 2λ

Since λ cannot equal zero, we can conclude that there are no critical points within the interior of D.

However, we need to check the boundary of D for critical points. The boundary is defined as x² + y² = 4.

Let's find the critical points on the boundary:

Substituting x² + y² = 4 into f(x, y):

f(x, y) = √(4 - x² - y²)

To find the absolute minimum and maximum on the boundary, we need to find the extremum points by analyzing the function along the boundary.

Using techniques such as Lagrange multipliers or parameterization, we can find that the absolute minimum occurs at (x, y) = (-2, 0), and the absolute maximum occurs at (x, y) = (2, 0).

Therefore:

a = -2

b = 0

The absolute minimum of f(x, y) is 0, and the absolute maximum is 2.

Please note that this solution assumes that the question is asking for critical points and extrema on the boundary of D, not at corner points. If the question intends to ask for extrema at corner points as well, further analysis would be needed.

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This reaction is reversible, and displacing the equilibrium to the rightnormally involves using a large excess of the acid, a strategy in accord with theLe Chatelier principle.(14.8)For example, 1-bromobutane may be prepared by heating 1-butanol with hydrobromicacid, HBr, in the presence of sulfuric acid (Eq. 14.9). The mechanism for thisreaction is known to occur in two steps, the first being protonation of the alcohol togive the oxonium ion 1 via a Lewis acid-base reaction (Eq. 14.10). This oxonium ionthen undergoes displacement by the bromide ion to form 1-bromobutane and water.This process is an SN2 reaction in which water is the leaving group and bromide ion isthe nucleophile. The sulfuric acid serves two important purposes: (1) It is a dehydratingagent that reduces the activity of water and shifts the position of equilibrium tothe right, and (2) it provides an added source of hydrogen ions to increase the concentrationof oxonium ion 1. The use of concentrated hydrobromic acid also helps toestablish a favorable equilibrium.No reaction occurs between 1-butanol and NaBr in the absence of strong acidbecause leaving groups in nucleophilic substitution reactions must be weakly basic(Sec. 14.1), as is water in Equation 14.10. If the reaction of 1-butanol and NaBr were tooccur (Eq. 14.11), the leaving group would necessarily be the strongly basic hydroxideion, a poor leaving group. Thus the forward reaction depicted in Equation 14.11 doesnot occur. On the other hand, the reverse reaction between 1-bromobutane andhydroxide proceeds readily because the leaving group in this reaction is the weaklybasic bromide ion.The mixture of hydrobromic acid and sulfuric acid may be prepared by eitheradding concentrated sulfuric acid to concentrated hydrobromic acid or by generatingthe hydrobromic acid in situ by adding concentrated sulfuric acid to aqueous sodiumbromide (Eq. 14.12). Both of these methods work well and give good yields of thealkyl bromide from low-molar-mass alcohols. The method of generating HBr in situis not effective with higher-molar-mass alcohols because of their low solubility inconcentrated salt solutions, so concentrated (48%) hydrobromic acid is used instead.Although the presence of concentrated sulfuric acid promotes the formation ofthe alkyl bromide, several side reactions involving sulfuric acid and the alcohol canoccur. One of these is esterification of the alcohol by sulfuric acid to form an alkylhydrogen sulfate 2 (Eq. 14.13).This reaction is reversible, and the position of the equilibrium is shifted tothe left, regenerating the alcohol from 2 as the alkyl bromide is produced. Theformation of 2 itself does not directly decrease the yield of alkyl bromide; rather,2 undergoes other reactions to give undesired by-products. For example, it sufferselimination on heating to give a mixture of alkenes (Eq. 14.14). It may also reactwith another molecule of alcohol to give a dialkyl ether by an SN2 reaction in whichthe nucleophile is ROH (Eq. 14.15). Both of these side reactions consume alcohol,so the yield of alkyl bromide is decreased. Fortunately, these side reactions may beminimized for primary alcohols by controlling the temperature of the reaction andthe concentration of sulfuric acid.It is necessary to use different procedures to prepare secondary alkyl bromidesfrom secondary alcohols because such alcohols are easily dehydrated by concentratedsulfuric acid to give alkenes by way of Equations 14.13 and 14.14. In fact, the acidcatalyzeddehydration of secondary and tertiary alcohols is a common method forsynthesizing alkenes (Sec. 10.3). This problem may be circumvented by using concentratedhydrobromic acid; however, it is better to prepare secondary alkyl bromidesby the reaction of secondary alcohols with phosphorus tribromide, PBr3 (Eq. 14.16).PREPARATION OF 1-BROMOBUTANE1. Describe the method by which hydrogen bromide is prepared for use in this experiment.2. Determine the limiting reagent for the conversion of 1-butanol to 1-bromobutane and the theoretical yield of product.3. Is this reaction an SN1 or SN2 process? How will the mechanism be confirmed experimentally?4. Write the structures of two possible side products that might be formed in this reaction.5. What is the purpose of the following experimental techniques, and where is each used in the preparation?a. heating at reflux.b. simple distillation.c. adding anhydrous sodium sulfate.6. List the possible effects of inhaling excessive amounts of 1-butanol.7. The flash points (C) of 1-butanol and 1-bromobutane are and , respectively.8. What action should you take if 1-butanol gets on your skin?9. Indicate whether the following statement is true (T) or false (F): Water is an appropriate medium for extinguishing fires involving 1-bromobutane. Decompose 549 two ways