The answers to all parts are shown below.
The law of uninhibited decay is a first-order chemical reaction, which means that the rate of the reaction is proportional to the concentration of compound A.
The rate law can be written as:
rate = k[A]
where k is the rate constant and [A] is the concentration of compound A.
From the given data, we can use the following equation to determine the rate constant:
ln([A]t/[A]0) = -kt
where [A]t is the concentration of compound A at time t, [A]0 is the initial concentration of compound A, k is the rate constant, and t is the time.
Using the given data:
[A]t = 0.37 M
[A]0 = 0.40 M
t = 30 minutes = 0.5 hours
ln(0.37/0.40) = -k(0.5)
k = 0.0486 h⁻¹
(a) How much of compound A will remain after 2 hours?
Using the same equation and substituting the known values:
ln([A]t/[A]0) = -kt
ln([A]t/0.40) = -0.0486 x 2
[A]t/0.40 = e⁻(⁹⁷² /¹⁰⁰⁰⁰)
[A]t = 0.25 M
Therefore, after 2 hours, 0.25 M of compound A will remain.
(b) How long will it take until 0.10 M of compound A remains?
Substituting the known values into the equation again:
ln([A]t/[A]0) = -kt
ln(0.10/0.40) = -0.0486t
t = 4.26 hours
Therefore, it will take approximately 4.26 hours until 0.10 M of compound A remains.
(c) After 2 hours, the amount of compound A remaining will be 0.25 M.
Learn more about Rate Law here:
https://brainly.com/question/30379408
#SPJ1
Solve each proportion 2/r=12/18
Answer:
r = 3
Step-by-step explanation:
starting with
2 / r = 12 / 18. we cross multiply
18 * 2 = 12 * r
36 = 12 * r
and divide by 12 to isolate "r"
36 / 12 = r
Then r = 3
Which graph shows u + v for the given vectors u and v?
Answer:
The answer is A
Step-by-step explanation:
When you move v's tail to u's head, you see that the vectors align up.
The graph shows (u + v) for the given vectors u and v will be Graph A.
What is vector ?A vector is an object that has both a magnitude and a direction. Magnitude defines the size of the vector. It is represented by a line with an arrow, where the length of the line is the magnitude of the vector and the arrow shows the direction.
We have,
Four graphs and we have to tell which is the correct graph for (u + v).
So,
To add two vectors, add the corresponding components.
i.e. The sum of u and v vector = ( u₁ + v₁, u₂ + v₂)
i.e.
Let u = (u₁, u₂) and
v = (v₁, v₂)
Now,
(u + v) = ( u₁ + v₁, u₂ + v₂)
So,
From Graph A,
We have,
u = (1, 4) and v = (2, -2)
i.e.
u₁ = 1,
u₂ = 4,
v₁ = 2,
v₂ = -2
So,
Using the addition method of vector,
i.e.
(u + v) = ( u₁ + v₁, u₂ + v₂)
Substituting values,
(u + v) = [( 1 + 2), (4 + (-2))]
We get,
(u + v) = (3, 2)
So,
The graph A represents the correct points of (u +v).
Hence, we can say that the graph shows (u + v) for the given vectors u and v will be Graph A.
To know more about vectors click here
https://brainly.com/question/24256726
#SPJ2
What is the surface area of a regular square pyramid with a slant height of 12 cm in a lateral edge of 13 cm?
Answer:
340 cm squared
Step-by-step explanation:
[tex]l=2\sqrt{13^{2} -12^{2} }=10cm[/tex]
[tex]A=l^{2} +2l*h\\10*10+2*10*12=340cm^{2}[/tex]
Theresa has $708 in her account and wishes to throw a party. She plans to include the following:
Purchase
Cost ($)
Decorations
76.92
Catering
150.66
Musicians
242.15
Refreshments
123.36
Venue
260.47
When Theresa makes the calculations, she finds that she cannot afford everything that she would like to have. What is the cheapest aspect of the party that she can eliminate to keep from overdrawing her account?
Answer:
Get rid of catering with everything u are in debt by 145.56 so get rid of catering and u r good
Step-by-step explanation:
what is two plus eight
Answer:
2 + 8 = 10
Step-by-step explanation:
Hope it helps you!
Answer:
10 is the answer
Step-by-step explanation:
Select the correct answer. What is the solution to the equation?
square root of x-3 + 1 = 6
64
46
28
22
Answer:
Correct answer is 28
Step-by-step explanation:
The solution to the equation is 8.
What is a solution?Solutions are the values of an equation where the values are substituted in the variables of the equation and make the equality in the equation true.
We have,
x - 3 + 1 = 6
Solve for x.
x - 2 = 6
x = 6 + 2
x = 8
We can cross-check.
x - 3 + 1 = 6
8 - 3 + 1 = 6
9 - 3 = 6
6 = 6
True
Thus,
The solution is 8
Learn more about solutions of equations here:
https://brainly.com/question/545403
#SPJ2
Help needed with this as soon as possible
Answer:
1
Step-by-step explanation:
g(-3)=-2(-3)²+3(-3)
=-18-9
=-27
The mayor of a town has proposed a plan for the annexation of a new community. A political study took a sample of 800 voters in the town and found that 51% of the residents favored annexation. Using the data, a political strategist wants to test the claim that the percentage of residents who favor annexation is more than 47%. Determine the P-value of the test statistic. Round your answer to four decimal places.
hope this helps!!
mark me brainlist? this took a lil bit
Only one of the comparisons below is correct. Which is correct? What benchmark was used in your answer?
ANSWERS ARE:
2/3<1/2; I used 1/2 as a benchmark.
1/2=3/5; I used 1/4 as a benchmark.
2/3<9/10; I used 3/4 as a benchmark.
3/4<2/3; I used 1/2 as a benchmark.
Answer:
2/3<9/10; I used 3/4 as a benchmark.
Step-by-step explanation:
2/3<1/2; I used 1/2 as a benchmark.
2/3 = 0.(20/3) = 0.667
1/2 = 0.(10/2) = 0.5
So this is wrong, as 0.667 > 0.5.
1/2=3/5; I used 1/4 as a benchmark.
1/2 = 0.(10/2) = 0.5
3/5 = 0.(30/5) = 0.6
0.5 != 0.6, so this is wrong.
2/3<9/10; I used 3/4 as a benchmark.
2/3 = 0.(20/3) = 0.667
9/10 = 0.(90/10) = 0.9
So this is correct, as 0.667 < 0.9
3/4<2/3; I used 1/2 as a benchmark.
3/4 = 0.(30/4) = 0.75
2/3 = 0.(20/3) = 0.667
0.75 > 0.667, so this is wrong.
[tex]3(x+2)^2-6=21[/tex]
What number is missing from this factor tree for the prime factorization of 328?
A. 39
B. 41
C. 42
D. 82
Answer: Your Answer Is A) 41
Step-by-step explanation:
328
^
2 x 164
^
2 x 82
^
2 x 41Geometry problem above^^^ In the figure at the right FGH ~ KLJ....
Answer:
x = 12
y = 4.5
Step-by-step explanation:
Since ∆FGH ~ ∆KLJ, therefore, we would have the following proportion:
[tex] \frac{FG}{KL} = \frac{GH}{LJ} = \frac{FH}{KJ} [/tex]
[tex] \frac{9}{y} = \frac{x}{6} = \frac{6}{3} [/tex]
✔️Let's solve for x using:
[tex] \frac{x}{6} = \frac{6}{3} [/tex]
Multiply both sides by 6
[tex] \frac{x}{6}*6 = \frac{6}{3}*6 [/tex]
[tex] x = \frac{6*6}{3} [/tex]
[tex] x = 12 [/tex]
✔️Solve for y using:
[tex] \frac{9}{y} = \frac{6}{3} [/tex]
Cross multiply
[tex] y*6 = 3*9 [/tex]
6y = 27
y = 27/6
y = 4.5
Which line is the line of reflection?
Answer:
b
Step-by-step explanation:
because those two triangles are face to face
√ 3 x + 4 = √ 3 x + 4 3 x + 4 = 3 x + 4
Answer
Step-by-step explanation: =/
Suppose you want to study the relationship between smoking and cancer. You assume that smoking is a cause of cancer. Studies have shown that there are many factors affecting this relationship, such as the number of cigarettes or the amount of tobacco smoked every day; the duration of smoking; the age of the smoker; dietary habits; and the amount of exercise undertaken by the individual. All of these factors may affect the extent to which smoking might cause cancer. These variables may either increase or decrease the magnitude of the relationship. Which statement is false?
a. In the above example cancer is the dependent variable.
b. In the above example cancer is an independent variable.
c. In the above example the extent of smoking is an independent variable.
d. In the above example all the variables that might affect the relationship between smoking and cancer, either positively or negatively, are extraneous or mediating/moderating variables.
Answer:
The correct answer is:
In the above example cancer is an independent variable. (b)
Step-by-step explanation:
In order to explain the choice made, let m first explain what independent and dependent variables are:
Independent variable: An independent variable is a variable that is under the direct control of the experimenter, and can be changed at will. In this example, the number of cigarettes or amount of tobacco smoked is the independent variable because it can be manipulated at will, to determine the outcome of the dependent variable.
Dependent variable: A dependent variable is a variable that the experimenter sets out to study. The independent variable is not under the direct manipulation of the experimenter but has values that come about as a result of the change of the independent variable. In this example, cancer is the dependent variable, because it is the result of the manipulation of the amount of tobacco.
Therefore, it is not true to say that cancer is the independent variable as seen in option b
... me no like math...
Answer:
i got 61.27
Step-by-step explanation:
quater circumference [tex]=\frac{3.14 * 22}{4}[/tex]
= 17.27
20+2+2+(20-11)+11+17.27 = 61.27
Which of the expressions below is greater than 100? Select all that apply.
A) 41.588 + 48.112
B) 25.768 + 77.312
C) 93.546 + 7.015
D) 297.354 – 195.81
E) 112.457 – 11.982
Answer:
The answer is b, c, d and e
I am having trouble on figuring out how to write this out to solve it.
The domain is (-infinity,1)(1, infinity) or {x|X=/1} the dash goes through the equal sign
the formula may be h^2x h squared x for expanding using sum/difference
find the area of the trapezium whose parallel sides 24 cm and 20 cm and the distance between them is 15 cm.
Answer:
330
Step-by-step explanation:
A=a + b / 2 x h
a = 24, b = 20, h = 15
24 + 20 divided by 2 times 15
44 divided by 2 time 15
22 times 15 = 330
Noah bought 3 cans of paint and 1/2 of a pint of special paint additive formulated to reduce mildew. Before painting his house, he divided the additive equally among the 3 cans of paint. How much additive did he put in each can?
Step-by-step explanation:
Amount of additive in each can
= Total amount of additive / Number of cans
= (1/2 of a pint) / (3)
= 1/6 of a pint.
Noah put 1/6 of a pint of additive in each can.
The volume of a cone-shaped hole is 1471 ft. If the hole is 9 ft deep, what is the radius of the hole
Please don’t put random numbers i just want the answer, I’ll make you brainliest
The volume πr^2*height/3=1471
π*r^2=1471/9*3
π*r^2=490.33(I'm rounding all my numbers to the hundredths digit)
r^2=490.33/3.14(taking 3.14 for pi)=about 156.16
r= sqrt 156.16=about 12.5
Again this answer is not precise but I rounded everything to the hundredths digit because pi is never ending. I hope it helped!
The graphs below have the same shape. What is the equation of the blue graph? 
Answer:
c
Step-by-step explanation:
The first equation of a system of equations is y = -3x + 2. The graph of the system has no solution. Write a possible second equation for the system.
Answer:
see below.
Step-by-step explanation:
For a system of equation to not have a solution, the pair of lines will never intersect. For two lines to never intersect, their slopes will be parallel.
The second equation can be as simple as y = -3x.
The only equation it cannot be with a slope of -3 is y = -3x + 2. This is because that is the same equation and will therefore have an infinite number of solutions.
Your new computer cost $1,500, but it depreciates in value by about 18% each year. How much will your computer be worth in 6 years?
Answer: Nothing or 0
find the Sum and the product
of the root of the Equadration
1/3and 2/3
Answer:
sorry do not know
Step-by-step explanation:
.
Answer:
9x² - 9x +2
Step-by-step explanation:
general formula =x²-(sum of roots)x+(product of roots)
Three years ago A's age was double of B's
age. Seven years hence, the sum of their
ages will be 83 years. Find the present
age of A?
Answer:
present Age of " A " will be (x) = 45 years
present Age of " B " will be (y) = 24 years
Step-by-step explanation:
Age of " A " = x years
Age of " B " = y years
(Three years ago A's age was double of B's age.)
==> (x-3) = 2 * (y-3)
==> x - 2y = -6 + 3
==> x - 2y = -3 -------------(1)
(Seven years hence, the sum of their ages will be 83 years )
==> (x+7)+(y+7) = 83
==> x + y = 83 - 14
==> x + y = 69 ------------(2)
Subtract equ.(1) & equ(2)
==> -2y - y = -3 - 69
==> -3y = -72
==> y = -72/(-3)
==> y = 24
Keep value of y in equ(2)
==> x + 24 = 69
==> x = 69 - 24
==> x = 45
Question 5 of 5 0 3 4 5 6 7 8 9 10 Which of the following could be the number shown on the number line? O A A. V20 OB. √24 C. 27 D. 26
Answer:
hi may u send a pic?
Step-by-step explanation:
Answer: 24
Step-by-step explanation:
With every number starting with 2 count the number line up it doesn't past 5 or on 5 so it's not 5. It's past 4 so whats your answer?
Vitamin D is important for the metabolism of calcium and exposure to sunshine is an important source of vitamin D. A researcher wanted to determine whether osteoperosis was associated with a lack of exposure to sunshine. He selected a sample of 250 women with osteoperosis and an equal number of women without osteoperosis. The two groups were matched - in other words they were similar in terms of age, diet, occupation, and exercise levels. Histories on exposure to sunshine over the previous twenty years were obtained for all women. The total number of hours that each woman had been exposed to sunshine in the previous twenty years was estimated. The amount of exposure to sunshine was compared for the two groups.
Required:
a. Determine whether this is a controlled experiment or an observational study.
b. Identify the treatment variable.
Answer:
Vitamin D and Osteoporosis
a. This is an observational study. The researcher is trying to observe the two groups of women who suffer from osteoporosis. She did not apply any treatment on any group, as is the case with experimental researches.
b. The treatment variable is the amount of exposure to sunshine.
Step-by-step explanation:
This study is an observational research because the researcher lacks the control over the variables, especially the amount of exposure to sunshine. She is merely observing what has occurred previously. On the other hand, an experimental study will involve the application of some treatments to one group of women and then the recording of the effects. But in this case, the researcher merely recorded the effects that had occurred without applying any treatment to any group.
Select all expressions that are equivalent to 64^2/3
Answer:
16
Step-by-step explanation:
Answer:
27
Step-by-step explanation:
Determine what number to multiply the first equation by to form opposite terms for the x-variable. 2/5 x + 6y = -10 –2x – 2y = 40 Multiplying the first equation by will create opposite x terms.
Answer: 5
Step-by-step explanation: edge 2021
You can use the constant which if multiplied with the coefficient of x in first equation, ends up making it negative and of equal magnitude to the coefficient of x variable in second equation.
The first equation should be multiplied by the constant 5
How to choose what quantity to multiply the first equation?This method is actually called method of elimination to solve a system of linear equations.
We make one specific variable's coefficients of equal magnitude so that we can subtract or add the equations and eliminate that variable to make it easy to get the value of the other variable which will then help in getting the value of the first variable (if working in dual variable system).
If we have equations:
[tex]a_1x + b_1y = c_1\\a_2 x + b_2y = c_2\\[/tex]
then, if we want to eliminate variable x, then we have to multiply equation 1 with [tex]-\dfrac{a_2}{a_1}[/tex] which will make coefficient of x in first equation as [tex]a_1 \times -\dfrac{a_2}{a_1} = -a_1[/tex]
Then adding both equation will eliminate the variable x.
We could've skipped that -ve sign and at then end, instead of adding, we could've subtracted the equations.
Using above method for getting the needed constantThe system of equation we've got is
[tex]\dfrac{2}{5}x + 6y = -10\\\\-2x -2y = 40[/tex]
Thus, we have the constant needed = [tex]-\dfrac{a_2}{a_1} = -\dfrac{-2}{2/5} = 5[/tex]
The resultant system of equation we will get is:
[tex]2x + 30y = -50\\\\-2x -2y = 40[/tex]
Thus,
The first equation should be multiplied by the constant 5
Learn more about system of linear equations here:
https://brainly.com/question/13722693