Question 1 ( point) A 64g sample of Germanium-66 is left undisturbed for 12.5 hours. At the end of that period, only 2.0g remain. How many half-lives transpired during this time period? half-lives Answer = Blank 1:​

Answers

Answer 1

Answer:

2.5 half-lives

Step-by-step explanation:

Find [tex]t_{h}[/tex] in [tex]N(t)=N_{0}e^{-kt}[/tex] given [tex]N(t) = 2, N_{0} =64,t=\frac{25}{2}[/tex]

[tex]N(t)[/tex] is the amount after the time [tex]t[/tex], [tex]N_0[/tex] `is the initial amount, [tex]t_{h}[/tex] is the half-life

We know that after half-life there will be twice less the initial quantity:

[tex]N(t_{h})=\frac{N_{0} }{2}=N_{0}e^{kt_{h} }[/tex].

Simplifying gives [tex]\frac{1}{2} =e^{-kt_h} or k = -\frac{In(\frac{1}{2}) }{t_{h} } .[/tex]

Plugging this into the initial equation, we obtain that [tex]N(t)=N_{0}e^\frac{In(\frac{1}{2}) }{t_{h} }[/tex]or [tex]N(t)= N_{0} (\frac{1}{2})^\frac{t}{t_h}.[/tex]

Finally, just plug in the given values and find the unknown one.

From [tex]2=64(\frac{1}{2})^\frac{\frac{25}{2} }{t_h}[/tex], we have that [tex]t_h[/tex] = [tex]\frac{25 In (2)}{2 In (32)\\}[/tex]

So you should get: [tex]t_{h} =\frac{25 In (2)}{2 In (32)\\}=2.5.[/tex]

MARK ME AS BRAINLIEST IF YOU WISH
Answer 2

The number of half-lives that transpired during this time period is equal to 2.5 hours.

Given the following data:

Time = 12.5 hours.

Initial mass = 64 grams.

Remaining mass = 2.0 grams.

How to determine the number of half-lives.

Mathematically, the amount of a radiocative element that is remaining after time (t-hours) is given by this formula:

[tex]ln(\frac{A}{A_0} )=ln(\frac{1}{2} )\frac{t}{H}[/tex]

Where:

A is the amount remaining.Ao is the initial amount.H is the half-life.t is the time.

Substituting the given parameters into the formula, we have;

ln(2/64) = ln(1/2) × 12.5/H

-3.466 = -0.693 × 12.5/H

H = 12.5 × -0.693/-3.466

H = 12.5 × 0.1999

H = 2.5 hours.

Read more on half-life here: https://brainly.com/question/25750315


Related Questions

1344 divided by 16
(Pls ans)​

Answers

Answer:

84

Step-by-step explanation:

Answer:

84

Step-by-step explanation:

1344/16=84

PLS HELPPP
What value of x would make the following relation a function?
{(-3,-2),(2,3),(3,2),(x,2)}

A. -3
B. -2
C. 2
D. 3

Answers

A........................................

The second term in a geometric sequence is 12. The fourth term in the same sequence is 4/3 what is the common ratio in this sequence

Answers

Answer:

The common ratio in this sequence is 6:2 or 4:3

Step-by-step explanation:

hopes this heklps

(x2 – 3x + 2)/(4x - 16)

Answers

Answer:

Pretty sure it's x^2−3x+2/4x-16  

Step-by-step explanation:

98.8% of 668.49km NEED ANSWERS QUICK

Answers

Answer:

the answer would be  660.46812 km

Step-by-step explanation:

The computation is shown below:

According to the question it is mentioned what is the 98.8% of 668.49 km

So, it would be

= 98.8% of $668.49 km

= 98.8% × 668.49 km

= 660.46812 km

Hence, the answer would be  660.46812 km

Write an expression for the sequence of operations described below.
10 plus the quotient of 8 and u
Do not simplify any part of the expression.

Answers

Answer:

[tex]10 + \frac{8}{u}[/tex]

Step-by-step explanation:

Given

10 [tex]plus[/tex] the  [tex]quotient[/tex]of 8 and u

Required

Represent as a mathematical expression

Square out the operators

10 [[tex]plus[/tex]] the  [[tex]quotient[/tex]] of 8 and u

[tex]plus => +[/tex]

[tex]quotient => /[/tex]

Replace the operators with their signs

[tex]10 + \frac{8}{u}[/tex]

Is this right? Please help

Answers

Answer: I believe that is correct! good jobbb

Step-by-step explanation:

(9x10^10) - (4x10^10)

Answers

Answer: 50000000000 is your answer.

Step-by-step explanation:

Umm yea help me please:)

Answers

Just round the decimal up

8 friends go to Subway and each get 1/2 of a sandwich. How many sandwiches did they get altogether?

Answers

8 sandwiches just half the size

what shape can be formed from the following net?​

Answers

Answer:

A Triangular Prism    

Hope that helps!

Step-by-step explanation:

Answer: Triage

Step-by-step explanation:

The matrix is used to solve a problem. Which of the following would be a solution to the problem?

Answers

Answer:

(1,5)

Step-by-step explanation:

Hope this is right.

Answer:

It's (1,0)

Step-by-step explanation:

I got it right on the quiz

PLEASE HELP MEE it’s urgent

Answers

Answer:

positive9/50

Step-by-step explanation:

9/50

Answer:

the answer is 9/50 (fraction).

Step-by-step explanation:

hope this helped!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Can someone please help!!!

Answers

Answer:

its the 3rd one

Step-by-step explanation:

please help i will give brainliest

Answers

Answer : Line 1


Explanation: at the 1 hour mark on the x axis the line that goes through the 120 mark on the y axis is line 1

which table shows ordered pairs that satisfy the function y=4x-2

A x -2, 0, 2
y -4, -2, 0

B x -2, 0, 2
y 10, 6, 2

C x -2, 0, 2
y -8, 0, 8

D x -2, 0, 2
y -10, -2, 6

Answers

Answer: Choice D

==========================================================

Explanation:

If you plug in x = -2, then,

y = 4x-2

y = 4(-2)-2

y = -8-2

y = -10

This shows that the answer must be choice D, as this is the only answer that has x = -2 lead to y = -10. Note the first column of table D.

We could stop here if you wanted.

----------------------

If we kept going and plugged in x = 0, then,

y = 4x-2

y = 4(0)-2

y = 0-2

y = -2

We have x = 0 lead to y = -2. This matches with the second column of table D.

-----------------------

Lastly, if we plugged in x = 2, then we get,

y = 4x-2

y = 4(2)-2

y = 8-2

y = 6

So the third column of table D is also confirmed.

The factors of a polynomial are (x + 3x - 2)(x+ 7) The polynomial has been graphed. How do the zeros relate to the factors?

A. The zero is the sum of the numbers inside the parenthesis

B. There is no relationship between the factors and the zeros.

C. The number inside each parenthesis are the zeros of the equation.

D. If you set each factor equal to 0 and solved you would get the zeros.​

Answers

Answer:

its C I am pretty sure about it

Answer:

D: If you set each factor equal to 0 and solved you would get the zeros.

Step-by-step explanation:

Completed it on PL also because 0 should be base

the tax on a purchase of $20 is $2.80. How much tax will there be on a purchase of $45.50?

Answers

Answer:

$6.37

Step-by-step explanation:

You divide 2.80 by 20 to find the percentage of tax then you simply multiply your percentange by the cost. In this problem the tax was 14% or .14, so you multiply .14 by 45.50 to find the amount of tax on the purchase

But least to greatest

Answers

Answer:

8.933,8.96,9.05,9.065,9.08,9.1

Step-by-step explanation:

Make a equation for the scatter plot line

Answers

Answer:

y = -7.2x + 540

Step-by-step explanation:

to find the slope I used the x-and-y intercepts: (0, 540) and (75, 0)

slope = 540/-75 or -7.2

what is the square root of -20

Answers

Answer:

4.47213595

Simplify in the tenths place and get 4.47

Step-by-step explanation:

HELP HELP
Tommy rides in a motorboat against a river current for 25 km. Then he returns to his starting point by floating down river on a raft. Tommy travels 10 hours less on the motorboat than on the raft. Find the speed of the river current if the speed of the motorboat in still water is 12 km/h.

Answers

The speed of current is [tex]\rm 2 \:km/h[/tex].

What is the relation between distance,speed and time?

The relationship between distance, time and speed can be presented as:

[tex]\begin{aligned} \rm Distance &= Speed \times Time\\\\Speed &= \dfrac{\rm Distance}{Time} \\\\\rm Time &= \dfrac{\rm Distance}{\rm Speed} \end[/tex]

Calculations:

Given:

[tex]\begin{aligned} \rm Distance\: traveled\: on\: motorboat &= 25\:km\\\rm Speed\:of\:motorboat\:in\:still\:water &= 12\:km/h \end[/tex]  

 

Let the speed of the current be [tex]\rm x[/tex]

 

The speed of the boat traveling against the current is [tex]{(12 -\rm x) km/h}[/tex]

 

Time spent on motorboat is 10 hours less than time spent on raft.

Therefore:

[tex]\rm \dfrac{25km}{x\:km/h} - \dfrac{25km}{(12 - x)km/h} = 10[/tex]


The equation obtained will be:

[tex]\dfrac{25}{\rm x} - \dfrac{25}{(12-\rm x)} - = 10[/tex]

 

Multiplying both sides of the equation by [tex]\rm x(12 - x )[/tex]

[tex]\begin{aligned} \rm 25(12 - x) - 25x &= 10\times \rm x(12 - x)\\\\300 - 25x - 25x &= 120x - 10x^2\\\\300 - 50x &= 120x - 10x^2\\\\10x^2 - 120x - 50x + 300 &= 0\\\\10x^2 - 170x +300 &= 0\end[/tex]

Dividing the equation by 10

[tex]\rm x^2 - 17x + 30 = 0[/tex]

On factoring the equation,

[tex]\rm =x^2 - 2x -15x + 30 = 0\\\\=x(x - 2) -15(x - 2)\\\\=(x - 2)(x - 15)[/tex]

The values of x is 2 and 15.

Since speed of current i.e  [tex](12 -\rm x)km/h[/tex] cannot be negative, [tex]\rm x = 2[/tex] is the only acceptable value.

 Therefore the speed of current is 2 km/h.

Learn more about the topic here:

https://brainly.com/question/2292310

Which equation represents the function f(x) = (1.6)x after it has been translated 5 units up and 9 units to the right?

Answers

g(x) = (1.6)x − 9 + 5

Answer:

It's C. g(x) = (1.6)x − 9 + 5

Step-by-step explanation: hope it helps ^w^

Using lengths a, b, and c in the right triangle shown, how are the trigonometric functions of defined?

Answers

We need to see the triangle to answer this question.

Answer:

take a pic.of question

Step-by-step explanation:

gotta see the triangle

Given that A and I are the centers of the congruent circles shown below, compare the quantity in column A with the quantity in column B. Choose the best answer. The quantity in column A is greater. The quantity in column B is greater. The two quantities are equal. The relationship cannot be determined from the information given.

Answers

Answer: The two quantities are equal

Step-by-step explanation:

Edge2021

C. The two quantities are equal

Step-by-step explanation:

Edge 2020 2021

What percent of $80 is $20

Answers

Answer: $20$20​ is $25\%$25%​ of $80$80​.

Step-by-step explanation:

25

Please help when Kevin bought a new office phone, he borrowed $1,200 at a rate of 18% for 9 years

Answers

Answer:

where is the rest of the questions

Use each number in the box once to complete the division
5÷6,206

Answers

Answer:

i believe it is 1,241.2

Step-by-step explanation:

well you use long division.

Don operates a small craft store in which he sells other peoples crafts. He takes a 45% commission from the sales of all crafts. If he earns $958.00 Commission last week, how much did he sell?

Answers

Answer:

2,128

Step-by-step explanation:

958=45/100 x

958= 0.45* x

x=958/0.45

x=2,128 approximately

Hope that helps!

pls answer this-.....​

Answers

AnswerS:

Let A be the surface area, b the base, h the height;

h₁=8.4 cm

h₂=7.8 cm

b= 9 cm

A= 3(1/2bh₁)+1/2 bh₂

A=3(1/2(9)(8.4))+1/2 (9)(7.8)

A= 148.5 cm³

Answer:

Step-by-step explanation:

The figure given above is a square pyramid, having a square base and 4 triangular faces on the sides that are of the same dimensions.

Surface area of the square pyramid is given as:  

Where,

B.A = Base Area of the pyramid = 9*9 = 81 in²

P = perimeter of the base = 4(9) = 36 in

L = slant height of pyramid = 9.2 in

Plug in the values into the given formula to find the surface are

Other Questions
I need help with this because im kinda really d_mb :)1) Article 3 of the Florida Constitution creates a Florida State Legislature composed of how many houses? _________ 2) According to the Preamble to the current Florida constitution, who ordained and established the Constitution? _____________ 3) How many branches of government does Floridas constitution establish? ______ 4) What branches of government are there in the Florida constitution? (Name the branches) _____________________________________________ 5) Why would the Florida constitution be longer than the U.S. Constitution? ____________________________________________________________ 6) According to the Florida Constitution, municipal legislators must be ________________________________ 7) Name three (3) state related functions that counties carry out: A) ______________________________________ B) ______________________________________ C) ______________________________________ 8) The center of county government is usually in a city or town called the Isabel has 6.75 bags of coffee. A full bag weighs 5.2 pounds. How many pounds of coffee does Isabel have? *11.7711.9531.535.1which one ^ Which triangles are similar?232313/12673Trianglo A3639152862176715Triangle cTrianglo BO A. Triangles A, B, and COB. Triangles B and CO C. Triangles A and BD. Triangles A and CPREVIOUS Find the slope of a line that passes through the points (3,3) and (9, 1). Please simplify any fractions if you have them in your answer. Wrong answers only!!! What is the main source of surface water turning into underground water? Help me Please I will give brainliest! (please dont answer if you dont know) What functions do interest groups serve? Anne believed that deep down everyone was good. Do you agree with her or disagree with her? Why? To what was the ancient Egyptian writer referring in this hymn?The pharaohThe Nile riverThe sun God, ReThe Giza pyramid 2. The conditions faced by the Indian laborers described in the passage are most similar to those of(A)enslaved Africans in North America(B)bureaucrats serving in song China(C)guild members in European cities(D)merchants involved in the trans-Saharan trade What conclusion can you draw from the results shown?A)The amount of the drug was decreased to achieve the same effect.B) The mouse is in a state of tolerance.C) The mouse is suffering from withdrawal symptoms.D) The amount of drug injected was the same throughout the 7 weeks.Answer and I will give you brainiliest PLS REPLY ASAP WILL MARK BRAINLIEST Which of these sounds do you associate with happiness? Check any that apply.musicsounds in naturelaughterthe cheering of a crowda loved ones voicean ice cream truck Which is more dangerous?Lions or Cats???? When you analyze a prompt, you should mirror the language as closely as possible to the language of theprompt so that you are sure to write a clear thesis or claim. This helps you to know what kind of relevant textinformation to look for when you read your sources. When you write your essay, you can goback to your thesis and revise it to make the sentence a complex or compoundsentence that uses a colon.TrueFalse 33114"33A) right scaleneB) acute scaleneC) obtuse isoscelesD) equilateral What's the answer to this questions? 9 + 15mfactorisation of algebraic expression that contain common factor Here is an expression: 43^xa. Evaluate the expression when x = 2b. Evaluate the expression when x = 4. HELPPP PLZZZZ NOWWW !!!!!!!