Answer:
$ 20Step-by-step explanation:
[tex]1week \: = 5 \\ 4 \: weeks = x \\ \\ x = 20[/tex]
hope this helps you.
Can I have the brainliest please?
Have a nice day!
When electricity (the flow of electrons) is passed through a solution, it causes an oxidation-reduction (redox) reaction to occur. If the solution contains a metal cation such as Ag+, the flow of electrons will reduce the silver ion, causing solid silver to plate onto the electrode. The amount of metal plated depends on the number of electrons passed. The total charge of a mole of electrons is 96, 485 coulombs (C) and 1 ampere = 1 coulomb/second (C/s).
What mass of Cu(s) is electroplated by running 28.5 A of current through a Cu2+ (aq) solution for 4.00 h? Express your answer to three significant figures and include the appropriate units.
How many minutes will it take to electroplate 37.1 g of gold by running 5.00 A of current through a solution of Au+(aq)? Express your answer to three significant figures and include the appropriate units.
Answer:
a. 135 g
b. 60.6 min
Step-by-step explanation:
a. What mass of Cu(s) is electroplated by running 28.5 A of current through a Cu2+ (aq) solution for 4.00 h? Express your answer to three significant figures and include the appropriate units.
The chemical equation for the reaction is given below
Cu²⁺(aq) + 2e⁻ → Cu(s)
We find the number of moles of Cu that are deposited from
nF = It where n = number of moles of electrons, F = Faraday's constant = 96485 C/mol, I = current = 28.5 A and t = time = 4.00 h = 4.00 × 60 min/h × 60 s/min = 14,400 s
So, n = It/F = 28.5 A × 14,400 s/96485 C/mol = 410,400 C/96485 C/mol = 4.254 mol
Since 2 moles of electrons deposits 1 mol of Cu, then 4.254 mol of electrons deposits 4.254 mol × 1 mol of Cu/2 mol = 2.127 mol of Cu
Now, number of moles of Cu = n' = m/M where m = mass of copper and M = molar mass of Cu = 63.546 g/mol
So, m = n'M
= 2.127 mol × 63.546 g/mol
= 135.15 g
≅ 135 g to 3 significant figures
b. How many minutes will it take to electroplate 37.1 g of gold by running 5.00 A of current through a solution of Au+(aq)?
The chemical equation for the reaction is given below
Au⁺(aq) + e⁻ → Au(s)
We need to find the number of moles of Au in 37.1 g
So, number of moles of Au = n = m/M where m = mass of gold = 37.1 g and M = molar mass of Au = 196.97 g/mol
So, n = m/M = 37.1 g/196.97 g/mol = 0.188 mol
Since 1 mol of Au is deposited by 1 moles of electrons, then 0.188 mol of Au deposits 0.188 mol of Au × 1 mol of electrons/1 mol of Au = 0.188 mol of electrons
We find the time it takes to deposit 0.188 mol of electrons that are deposited from
nF = It where n = number of moles of electrons, F = Faraday's constant = 96485 C/mol, I = current = 5.00 A and t = time
So, t = nF/It
= 0.188 mol × 96485 C/mol ÷ 5.00 A
= 18173.30 C/5.00 A
= 3634.66 s
= 3634.66 s × 1min/60 s
= 60.58 min
≅ 60.6 min to 3 significant figures
A right triangle has a hypotenuse of 15 cm. What is the length for the missing leg if one of the two legs of the triangle is 5?
Answer:
The other leg is 12 cm long.
Step-by-step explanation:
c
2
=
a
2
+
b
2
,
where:
c
is the hypotenuse, and
a
and
b
are the other two sides (legs).
Let
a
=
9 cm
Rearrange the equation to isolate
b
2
. Plug in the values for
a
and
c
, and solve.
b
2
=
c
2
−
a
2
b
2
=
(
15 cm
)
2
−
(
9 cm
)
2
Simplify.
b
2
=
225 cm
2
−
81
cm
2
b
2
=
144 cm
2
Take the square root of both sides.
b
=
√
144 cm
2
Simplify.
b
=
12 cm
Answer:
14.14 cm
Step-by-step explanation:
using the Pythagorean theorem:
?² = 15² - 5² = 225 - 25 = 200
? = √200 = 14.14 cm
When the new principal on a loan is $79,946.13 and the interest rate is 8 percent, the monthly payment is $587.20. Find the interest, the payment to principal, and the new balance. STEP 1: Find the interest.
9514 1404 393
Answer:
to interest: $532.97to principal: $54.23new balance: $79,891.90Step-by-step explanation:
The interest is found by multiplying the monthly rate by the balance on the loan. For the first month, the balance is the loan amount.
$79,946.13 × 0.08 ×(1/12) . . . . . one month = 1/12 year
= $532.97
The interest amount in the first payment is $532.97.
__
The amount of the first payment that goes to principal is what is left after the interest is paid:
$587.20 -532.97 = $54.23 . . . amount to principal
__
The new balance is the previous balance less the amount to principal:
$79,946.13 -54.23 = $79,891.90 . . . new balance
Mia's birthday party will cost $12 if she invites 4 guests. What is the maximum number of guests there can be if Mia can afford to spend a total of $15 on her birthday party?
Is 3/4 closer to 0 or 1?
Answer:
It is closer to 1
Step-by-step explanation:
3/4 is 1/4 away from 1, whereas 0 is 3/4 away from 3/4. So, 1 is closer.
The fraction 3/4 is closer to 1.
We have,
To determine whether the fraction 3/4 is closer to 0 or 1, we can compare the distances between 3/4 and 0, and between 3/4 and 1.
The distance between 3/4 and 0 is 3/4.
The absolute value of the difference is |3/4 - 0| = 3/4.
The distance between 3/4 and 1 is 1 - 3/4 = 1/4.
Since the distance between 3/4 and 1/4 (which is 1/4) is smaller than the distance between 3/4 and 0 (which is 3/4), we can conclude that 3/4 is closer to 1 than to 0.
In other words, if we were to plot the fractions 0, 3/4, and 1 on a number line, the distance between 3/4 and 1 would be smaller than the distance between 3/4 and 0.
Therefore,
The fraction 3/4 is closer to 1.
Learn more about fractions here:
https://brainly.com/question/24370499
#SPJ2
What is the area of parallelogram ABCD?13 square units14 square units15 square units16 square units
Answer:
13
Step-by-step explanation:
the equation for parrlelograms is base times hieght. the base is about 3 and the hieght is 4 and 1/3 (ish) so 3*4.3 would give the answer of 13 square units. I hope this helps?
Help me with my homework, please
Answer:
150°
Step-by-step explanation:
We know each angle in a equilateral triangle is 60° and that of a rectangle is 90° . So ,
[tex]\implies \angle ABC = \angle DBC + \angle ABD \\\\\implies \angle ABC = 90^o + 60^o \\\\\implies \boxed{\boxed{ \angle ABC = 150^o }}[/tex]
construct a rectangle (a and b of known length, d diagonal)
What is the difference of the rational expressions below?
6x _ 5
X-2 X
A. 6x2 -5x - 10
x(x - 2)
B. 6x-5
2X-2
c. 6x^2 -5x +10
x(x-2)
D. 6x-5
-2
I'm
C.) 6x^2-5x+10/x(x-2)
Find the mean, median and mode of the following data sets.
1. 79, 84, 92, 81, 86, 77, 95, 80, 88, 84
2. 8, 9, 9, 9, 9, 10, 11, 15
3. 16, 23, 18, 30, 32, 34, 8, 19, 21
Answer:
1.
mean= 84.6
median=84
mode=84
2.
mean=10.14
median=9
mode=9
3.
mean=22.3
median=21
mode=phi
Step-by-step explanation:
mean: the sum of of the quantities by their number
median: the median value after rearranging the values
mode: the value that occurs most frequently
in the second question
mean = (8+9+9+9+9+10+11+15)/8
median(even number) =(9+9)/2=9
mode=9
Answer:
for data set 1
1.mean-84.6
2.median-(84+84)/2 = 84
3.mode-84
for data set 2
1.mean-9.25
2.median-(9+9)/2 = 9
3.mode-9
for data set 3
1.mean-22.3
2.median-21
3.mode-no mode with this data set
hope this helped!!
Simplify (6x2 - 4x + 7) - (8x2 - 2x + 5) =
Answer:
−2x 2−2+2
Step-by-step explanation:
Dan bought 20 bunches of seedless green grapes for $48. How many bunches can Kali buy if she has $12?
5
29
4
6
Answer:
Quantity = 5 grapes
Step-by-step explanation:
Given the following data;
Quantity of grapes = 20
Cost = 48
To find the cost of each grape;
Cost of each grape = total cost/quantity
Cost of each grape = 48/20
Cost of each grape = $2.4
Now, to find how many grapes $12 can buy;
Quantity = total cost/cost of each grapes
Quantity = 12/2.4
Quantity = 5 grapes
Therefore, $12 can buy 5 grapes.
In the past year and a half, Gnarly the dog lost an average of 2/9 pound each month. Today, Gnarly weighs 14 pounds. How much did Gnarly weigh a year and a half ago?
Answer:
Weight before 18 month = 18 pound
Step-by-step explanation:
Given:
Current weight of dog = 14 pound
Weight lose each month = 2/9 pound
Total number of month = [tex]1\frac{1}{2}[/tex] year = 18 month
Find:
Weight before 18 month
Computation:
Total weight lose = Weight lose each month x Total number of month
Total weight lose = 2/9 x 18
Total weight lose = 4 pound
Weight before 18 month = Current weight of dog + Total weight lose
Weight before 18 month = 14 + 4
Weight before 18 month = 18 pound
You sold 500 shares of Intel for $26.75 per share. Your broker charges you a
commission of $2.75 per thousand dollars of stock bought or sold. How much
money will be credited to your account when you sell? (Remember, commissions
are subtracted out of your transaction.)
Answer: $13339.25
Step-by-step explanation:
Since 500 shares of Intel were sold for $26.75 per share, the total amount will be:
= 500 × $26.75
= $13375
Since the broker charges a
commission of $2.75 per thousand dollars of stock bought or sold, the amount charged by the broker on $13375 will be:
= $2.75 × 13
= $35.75
The amount that'll then be credited into ones account will be:
= $13375 - $35.75
= $13339.25
write the first five terms of the sequence an=3n^2
Answer:
2,1,0 is the sequence of its terms
What linear expression would you add to -4y+2 to have a sum of y
Answer:
4
Step-by-step explanation:
What type of correlation is shown in the graph?
Answer:
no correlation
Step-by-step explanation:
it shows no trend or a line thing
also i think your pic is upside down haha
pls help
its was on khan academy
i will mark u brainiest!!!
Answer:
[tex]14 units[/tex]
Step-by-step explanation:
[tex]Solution:-[/tex]
[tex]A(5,1)B(7,1)[/tex]
[tex]\sqrt{(x_{1}-x_{2} ) ^{2}(y_{2} -y_{1}x^{2} }[/tex]
[tex]AB=\sqrt{(7-5)^{2} +(1-1)^{2} }[/tex]
[tex]= \sqrt{2^{2} } =2[/tex]
[tex]BC=\sqrt{7-7^{2}+(6-1)^{2} }[/tex]
[tex]=\sqrt{5^{2} } =5[/tex]
[tex]perimeter=2(AB)+2(BC)[/tex]
[tex]= 2(2)+2(5)\\[/tex]
[tex]= 4+10= 14[/tex]
[tex]-----------[/tex]
hope it helps...
have a great day!!
In 2001, gas cost $1.85 per gallon. In 2008, the price was
220% higher than in 2001.
What was the cost of gas per gallon in 2008?
expanded form :32,456
Answer:
30,000 + 2,000 + 400 + 50 + 6
Step-by-step explanation:
[tex]\text{The expanded form of 32,456 would be 30,000 + 2,000 + 4,000 + 50 + 6.}[/tex]
[tex]\text{We would have to identify what each number stands for.}[/tex]
[tex]\text{For example, 3 in 32,456 stands for 30,000.}[/tex]
[tex]\text{Hence, following this rule, we can conclude that the answer above is correct.}[/tex]
[tex]\text{I hope I helped you suceed!}[/tex]
point a and point b are placed on a number line point a is located at -20 and point b is 5 less then point a Wich statement about point b is true
Answer:
Step-by-step explanation:
D beause less then 5 that means it gose down the grid
Mark and eight of his friends went out to
eat. They decided to split the bill evenly.
Each person paid $9. What was the total
bill?
I don’t know the answer
Answer:
(a+b) (a-b) =a^2 - b^2
In this question a=2, b=square root of 5
So 2*2=4 square root of 5 times square root of 5 is 5
4-5=-1
Answer:
I believe the answer is -1.
Step-by-step explanation:
So I distributed,
2 x 2 = 4
[tex]-\sqrt{5}[/tex] x 2 = [tex]-2\sqrt{5}[/tex]
[tex]\sqrt{5}[/tex] x 2 = [tex]2\sqrt{5}[/tex]
[tex]\sqrt{5}[/tex] x [tex]-\sqrt{5}[/tex] = -5
4 [tex]-2\sqrt{5}[/tex] + [tex]2\sqrt{5}[/tex] - 5 = ?
the radicals cancel out and 4 -5 = -1
Describe how to transform the graph of g(x)=ln(x) in the graph of f(x) = ln(-x)-9
Answer:
the answer is d because it's reflects
What is the range of y = 7x^2 + 14x – 9?
Answer:
-1,-16
Step-by-step explanation:
y=ax^2+box+c
Which statement about the ordered pairs (–2, 9), (0, 9) and (3, 9) is not true?
Answer:
The slope of these coordinates is 0.
It is a horizontal line.
Step-by-step explanation:
SOMEONE HELP ME WITH THISS
Answer:
/_ 12 is the angle of depression from the firefighter to the second story window.
Step-by-step explanation:
Hope it helps!
#CarryOnLearning
Answer:
2nd option is the correct answer
Step-by-step explanation:
[tex] \angle 12[/tex] is the angle of depression from the second story window to the firefighter.
PLEASE HELP PLEASE
A girls' choir is choosing a uniform for their concert. They can pick red, green or
purple sweaters, and they can pick tan, white or black skirts. The shoes they need
come in gold and black. Assuming all combinations are acceptable, how many
different combinations can the choir pick?
Answer:
18
Step-by-step explanation:
=============================================================
Explanation:
There are 3 colors to pick for the sweaters (red, green, purple).There are 3 colors for the skirts (tan, white, black)There are 2 colors for the shoes (gold, black)Multiply out those values mentioned to get the final answer: 3*3*2 = 9*2 = 18.
There are 18 different outfit combos.
---------------
Further explanation (optional section):
Let's say we only worried about the sweaters and shoes, and for now there's only one color for the skirt. We have 3 colors for the sweaters and 2 for the shoes. Imagine a table with 3 rows and 2 columns. Each row is a different color for the sweater and each column is a different color for the shoe. There are 3*2 = 6 cells inside the table. Each cell is a different outfit.
For instance, we could have R = red sweater and G = gold shoe. Then that means RG = red sweater + gold shoe outfit. So we'd have RG as one of the cells of this 6 cell table.
Now imagine that we laid out a table that is 6 by 3. The 6 is from the 6 outfits calculated earlier, and the 3 is now accounting for the colors of the skirts. We'd then have 6*3 = 18 combos total. Again, each cell inside the table represents a different outfit combo.
HELPPPPP WILLLLL AMRK BRAINLIESTTTTTT
A bin of 5 transistors is known to contain 2 that are defective. The transistors are tested one at a time until both defective transistors have been identified. Denote N1 the number of tests until the first defective is identified and N2 the number of tests until the second defective is identified. (a) Find the joint probability mass function of N1 and N2.
Answer:
sorry I donot know the answer never mind ok