|
Discussion: Homework Help Thread - Finals Season!
Member Since: 1/25/2012
Posts: 44,884
|
Quote:
Originally posted by ClarksonSlays
Can someone help me with Algebra II? It's Vertex form and Quadratic formula practice.
|
I think I can. Post the question.
|
|
|
ATRL Contributor
Member Since: 8/19/2013
Posts: 43,104
|
2. The equation C = 18.04T^2 – 71,495.6T + 70,837,298 can be used to represent the import of crude oil (in thousands of barrels a day) in a given year.
c) What was the minimum amount of oil imported each day? When did this occur? Explain your answer.
If you can help me with that, there's two more like it that I might need help with.
|
|
|
Member Since: 1/25/2012
Posts: 44,884
|
Quote:
Originally posted by ClarksonSlays
2. The equation C = 18.04T^2 – 71,495.6T + 70,837,298 can be used to represent the import of crude oil (in thousands of barrels a day) in a given year.
c) What was the minimum amount of oil imported each day? When did this occur? Explain your answer.
If you can help me with that, there's two more like it that I might need help with.
|
I'm not PRECISELY sure, but I think it's kind of a trial and error type of question. Just replace T with seconds (start from 1) and see at what time the minimum amount of oil is imported, according to the least number.
|
|
|
ATRL Contributor
Member Since: 8/19/2013
Posts: 43,104
|
Quote:
Originally posted by BabyCantYouSee
I'm not PRECISELY sure, but I think it's kind of a trial and error type of question. Just replace T with seconds (start from 1) and see at what time the minimum amount of oil is imported, according to the least number.
|
The way I learned it is that the minimum their looking for is the same as the minimum y value if the equation were graphed as a parabola, which can be found by putting the equation into vertex form, which I forgot how to do But I might do trial and error if all else fails.
|
|
|
Member Since: 8/29/2012
Posts: 22,883
|
Quote:
Originally posted by BabyCantYouSee
Chem question:
A compound contains 6.44 g of boron and 1.80 g of hydrogen. The molar mass of the compound is 27.64 g / mol. What is the molecular formula of the compound?
|
So the compound is of form B(x)H(y) where x and y are the subscripts of the chemical formula. We know the molar mass of the compound is 27.64 and that 10.81x+y=27.64. The closest integer values that satisfy this are 2 and 6. Furthermore, if you check the ratio of moles of boron and hydrogen, the ratio comes down to 1:3 which is essential 2:6.
6.44 g of Boron divided by 10.81 g /mol ~ .6
1.8 /1 g /mol is 1.8.
.6/1.8 = 1:3 which is the ratio of Boron's subscript to Hydrogen's subscript in the chemical formula.
The answer is B2H6.
Quote:
Originally posted by ClarksonSlays
2. The equation C = 18.04T^2 – 71,495.6T + 70,837,298 can be used to represent the import of crude oil (in thousands of barrels a day) in a given year.
c) What was the minimum amount of oil imported each day? When did this occur? Explain your answer.
If you can help me with that, there's two more like it that I might need help with.
|
I'm assuming you can't do calculus. Try the quadratic formula? Also remember the equation gives the import in a given year and they want the minimum imported each day.
|
|
|
Member Since: 1/25/2012
Posts: 44,884
|
OHHHHHH okay.
From ax ^ 2 + bx + c to f(x) = a (x - h ) 2 + k ?
Is that what you mean?
|
|
|
Member Since: 8/3/2010
Posts: 71,871
|
Quote:
Originally posted by ClarksonSlays
The way I learned it is that the minimum their looking for is the same as the minimum y value if the equation were graphed as a parabola, which can be found by putting the equation into vertex form, which I forgot how to do But I might do trial and error if all else fails.
|
I'm kind of busy doing organic chem hw but this should help
http://www.wikihow.com/Find-the-Maxi...unction-Easily
|
|
|
Member Since: 1/25/2012
Posts: 44,884
|
Quote:
Originally posted by SupahBass05
So the compound is of form B(x)H(y) where x and y are the subscripts of the chemical formula. We know the molar mass of the compound is 27.64 and that 10.81x+y=27.64. The closest integer values that satisfy this are 2 and 6. Furthermore, if you check the ratio of moles of boron and hydrogen, the ratio comes down to 1:3 which is essential 2:6.
6.44 g of Boron divided by 10.81 g /mol ~ .6
1.8 /1 g /mol is 1.8.
.6/1.8 = 1:3 which is the ratio of Boron's subscript to Hydrogen's subscript in the chemical formula.
I'm assuming you can't do calculus. Try the quadratic formula? Also remember the equation gives the import in a given year and they want the minimum imported each day.
The answer is B2H6.
|
I kind of get it. But can you explain to me step by step please? Sorry, lol. I'm a dummy when it comes to chem and I really need to pass this course with a high mark. Plus, my teacher is marking this and he wants us to show full work. :/
|
|
|
Member Since: 8/16/2011
Posts: 60,893
|
Quote:
Originally posted by ClarksonSlays
2. The equation C = 18.04T^2 – 71,495.6T + 70,837,298 can be used to represent the import of crude oil (in thousands of barrels a day) in a given year.
c) What was the minimum amount of oil imported each day? When did this occur? Explain your answer.
If you can help me with that, there's two more like it that I might need help with.
|
Um you need to differenciate it and set the equation equalt to 0 and that's your T answer, and then you replace in C. Beware of the units.
|
|
|
Member Since: 8/29/2012
Posts: 22,883
|
Quote:
Originally posted by BabyCantYouSee
I kind of get it. But can you explain to me step by step please? Sorry, lol. I'm a dummy when it comes to chem and I really need to pass this course with a high mark. Plus, my teacher is marking this and he wants us to show full work. :/
|
Sure. So like the first step I did was kinda cheating because you can't technically skip and assume the integers for the chemical formula are 2 and 6 based on one equation. You need to set up a system. So the first equation should come from the chemical formula BxHy and the molar mass given. So for one mole of this mystery compound, the amount of boron and hydrogen add up in total to 27.64 g/ mol of compound. So:
10.81x + 1.00 * y = 27.64
10.81 and 1.00 are the molar masses of Boron and Hydrogen. Then, your second equation comes from the other info given. Convert the grams of boron and hydrogen in the compound to moles of each. So:
6.44 g of Boron/ 10.81 g of Boron/mol of Boron = .6 mol of Boron
1.8 g of Hydrogen/1 g of Hydrogen/mol of Hydrogen = 1.8 mol of Hydrogen
So our new equation is : .6x = 1.8 y or x=3y. In other words, there are 3 times as many Hydrogen atoms in the compound as Boron. You just solve the system of equations next by substitution.
10.81x + y = 27.64
3x=y
|
|
|
Member Since: 8/18/2013
Posts: 20,070
|
me @ this thread right now:
|
|
|
Member Since: 1/25/2012
Posts: 44,884
|
Quote:
Originally posted by SupahBass05
Sure. So like the first step I did was kinda cheating because you can't technically skip and assume the integers for the chemical formula are 2 and 6 based on one equation. You need to set up a system. So the first equation should come from the chemical formula BxHy and the molar mass given. So for one mole of this mystery compound, the amount of boron and hydrogen add up in total to 27.64 g/ mol of compound. So:
10.81x + 1.00 * y = 27.64
10.81 and 1.00 are the molar masses of Boron and Hydrogen. Then, your second equation comes from the other info given. Convert the grams of boron and hydrogen in the compound to moles of each. So:
6.44 g of Boron/ 10.81 g of Boron/mol of Boron = .6 mol of Boron
1.8 g of Hydrogen/1 g of Hydrogen/mol of Hydrogen = 1.8 mol of Hydrogen
So our new equation is : .6x = 1.8 y or x=3y. In other words, there are 3 times as many Hydrogen atoms in the compound as Boron. You just solve the system of equations next by substitution.
10.81x + y = 27.64
x=3y
|
And by substitution, do you mean do the steps in your previous post? By the way, I have to round, right?
|
|
|
Member Since: 8/29/2012
Posts: 22,883
|
Quote:
Originally posted by BabyCantYouSee
And by substitution, do you mean do the steps in your previous post? By the way, I have to round, right?
|
Woops, I think I wrote the last equation wrong. My mistak (corrected in the previous post). It's:
3x= y.
So you would substitute using that equation.
10.81x + 3x = 27.81
Solve for x. And then y should be 3 times x.
|
|
|
Member Since: 1/25/2012
Posts: 44,884
|
Quote:
Originally posted by SupahBass05
Woops, I think I wrote the last equation wrong. My mistak (corrected in the previous post). It's:
3x= y.
So you would substitute using that equation.
10.81x + 3x = 27.81
Solve for x. And then y should be 3 times x.
|
I sent you a PM, lols.
|
|
|
Member Since: 12/15/2008
Posts: 38,248
|
Quote:
Originally posted by RatedG²
wtf is that? . I'm taking orgo now but I've never heard of such tomfoolery, sorry . Contact KB, she may know
|
Ugh, I know, I love Chemistry and I'm about to begin University as Chemistry Engineer, but I'm definetely thinking it's my teacher's fault, I don't find it in internet or any books. She might be thinking in another thing when she said that
Thanks anyway
|
|
|
Member Since: 8/1/2012
Posts: 11,608
|
If I have the equation x+y=4
How do I get the coordinates to plot on a diagram from it? would it be 0.4, 4,0?
Death at how basic my question is compared to the other ones asked 😫
|
|
|
Member Since: 8/16/2011
Posts: 60,893
|
Quote:
Originally posted by RihannaLoverrr
If I have the equation x+y=4
How do I get the coordinates to plot on a diagram from it? would it be 0.4, 4,0?
Death at how basic my question is compared to the other ones asked 😫
|
you can rearrange that as y=x-4
So for x=0, y=-4
for x=4, y=0
Plot those two points and join them together
|
|
|
Member Since: 8/1/2012
Posts: 11,608
|
Quote:
Originally posted by rihannafan
you can rearrange that as y=x-4
So for x=0, y=-4
for x=4, y=0
Plot those two points and join them together
|
Thank you!
|
|
|
Member Since: 8/19/2013
Posts: 15,127
|
My teacher gave me a bit extra time.....on that report I turned in was supposed to be due
He gave me until 12:00 Am..... i turned it in at 12:07am
procrastination is real
|
|
|
Member Since: 4/17/2012
Posts: 1,662
|
Hey guys. I have an integral equation that i can't seem to solve. I've been doing this for an hour and i can't seem to figure it out.
e^3X/(e^x)+1 dx.
Thanks in advance.
|
|
|
|
|