Chemistry -repost thank you in advance

62,266 results

Chemistry -repost thank you in advance

I have a bottle of 95% ethanol purchased from the manufacturer. Normally, when it is not stated, does it mean 95% w/w ethanol? I need to prepare 100ml of 40% v/v ethanol solution from 95% ethanol. Please show me the calculation steps. Thanks.


Known: Cyanaocetic acid Ka=3.55*10^-3 ionization equation: HC3H2NO2<==> H^+ + C3H2NO2^- Unknown: pH of 0.4M of Cyanaocetic acid How can I find out the pH of 0.4M of Cyanaocetic acid ? Is there another way solving for it other than using ICE chart? Please help me out.I ...

physics EM repost

Magnetic resonance imaging needs a magnetic field strength of 1.5 T. The solenoid is 1.8 m long and 75 cm in diameter. It is tightly wound with a single layer of 2.50-mm-diameter superconducting wire. What size current is needed? Thanks in advance

question repost damon

Since some tutors don't check back, i want to repost this to damon: what percent more than 1/3 is 3/5? It said 3/5 was wrong, and I tried but i don't know what happend

Bobpursley can you help me with my problems below?

I had problems from yesterday but I still don't get them can you help?do you want me to repost? repost: I cant find them.

Science [repost]

What is the difference between an ionic bond and a covalent bond? I just keep forgetting which one is which...any easy way to remember these? PS> I know that you're not supposed to repost until 24 hours but I really need this answer! Thanks -MC


Homework Help Forum: brain teaser help Current Questions | Post a New Question Answer this Question | Further Reading Posted by sam on Sunday, April 2, 2006 at 3:34pm. try to find the error. I couldn't; it's very hard. A B C D E F G H I J K L M N O P Q R S T U V W X Y Z did ...


Write formula equations and net ionic equations for the hydrolysis of sodium carbonate in water. Responses Chemistry - DrBob222, Friday, April 24, 2009 at 10:50pm The hydrolysis of Na2CO3 ends us as the hydrolysis of the carbonate ion. The molecular formula is Na2CO3 + HOH==...


need to apply the moral theory of rule utilitarianism in my essay but i don't really understand what it is. i tried google and wiki but it doesnt really provide me with clear meaning, or examples. could someone please explain to be as simple as possible what RULE utiliarianism...

Math - repost for Anonymous

Can someone show me the steps to these questions (I will provide the correct answers)? Thanks in advance. 1. When the polynomials 4x^3 + mx^2 + nx + 11 is divided by x + 2, the remainder is -7. When the polynomial is divided by x - 1, the remainder is 14. What are the values ...


on the 1st page can someone please help me??????? Its the 2nd and 3rd black dot next to my nasme. Even if this is a repost, more information needs to be given before we can adequately respond. Please repost with more information. Thanks for asking.

Science repost for help

Sciece (chemistry) - help, Tuesday, September 25, 2007 at 4:32pm what is the particle theory

ACCOUNTING (Advance Sales)

Hi: I am unsure of how to adjust Advance Sales. For Year End, DEC 31, 2011. If my Unadjusted Balance for advance sales is $324,000 and I am told the following: 75% of the balance in Advance Sales is for garments to be made and delivered in 2012; the remaining 25% is from sales...

Algebra pls. help

so i've already answered one of the questions i asked yesterday. thanks for the username damon. yeah it was a typo. I'm gonna repost a question. Please please... someone help me. *The first and the second term of a progression are "a" and "b" respectively. what is the third ...

chemistry [repost]

In a recrystallization of vanillin, can you purify a substance whose solubility decreases as the temperature increases? Any help is appreciated!


The case In Re: Guardianship of Schiavo is an example of: A. why only the elderly need advance directives. B. the importance of advance directives, even if someone is relatively young. C. a case involving anatomical gifts. D. what happens when a person leaves conflicting forms...

Chemistry - v/v versus w/w

Thanks a lot:) So just to confirm: normally for any chemical bought from manufacturer, if it is not stated, the % usually means v/v? Seems like for conc sulphuric acid, when it is stated 97% sulphuric acid, it means 97% w/w sulphuric acid? Thank you very much. Posted by annie ...

To Ron: Chemistry 12

I've deleted your 14 chemistry questions because you've made no attempt at answering them. This is not a site to dump homework questions like so much garbage to be disposed of. If you'd like to repost any of them with your answers, someone may be able to check them.


Repost:: sorry couldn't understand it What is the concentration of C2O4^-2 in a 0.370M oxalic acid solution? Ka1=5.6x10^-2 and Ka2=5.1x10^-5

Business Communication

"It is the case that good communicators advance more quickly in the company." Which of the following statements would be the best revision of this sentence? A. "It is the case that good communicators advance faster in the company. " B. "it is true that good communicators ...


Could someone please tell me where to find the 2008 AP Chemistry Multiple Choice for FREE ONLINE? Thank You in advance!

History *repost* (sorry!)

After the Gupta Empire collapsed, what group gained control of much of India? Muslims from Afghanistan Buddhists from China*** Christians from Ethiopia local Hindu princes Which of the following was NOT a part of the organization of the early Christian church? the pope the ...

social studies

"It is the case that good communicators advance more quickly in the company." Which of the following would be the best revision of this sentence? "It is the case that good communicators advance faster in the company." "It is true that good communicators advance more rapidly in...


It is the case that good communicators advance more quickly in the company.Which of the following would be the best revision of this sentence? a) "Good communicators advance more quickly in the company." b) "It is true that good communicators advance more rapidly in the ...

Physics Check

1.)The making of the nuclear reactor was an advance in a)Science *b)Technology c)none of the above 2.)The development of the airplane was an advance in a)Science b)Technology *c)none of the above 3.)The discovery of gravity was an advance in *a)Science b)Technology c)none of ...


Calculate the concentration, in percent by mass, of a refrigerant brine solution which is 4.03 M in NaCl with a density of 1.116 g mL-1. detailed answer, please, i don't understand how to do this at all!!!


Can you please look at my repost. I made an error in my question, so now I need your help for a different part of the question. :) Thanks. -Sadie


What is the boiling point of ethanol when the atmospheric pressure is 60kPa? I decided to repost this ? under Science instead of Chemistry. Thanks.


(-2x2y)3 * (5xy3)2 *I don't get this on at all!!! Are there any exponents in this one? If so, repost showing the caret to indicate the exponent. oh sorry I forget to do that.LOL!Here it is now: (-2x^2y)^3 * (5xy^3)^2 Are there any exponents in this one? If so, repost showing ...


Which of the following is NOT truly an advance directive? A. Living will B. Do not resuscitate order C. Advance funeral arrangements D. Designation of a health care surrogate is it B im confused

To Lynn,Alex,Physics_student,Natasha

Please refrain from reposting the same question within a short time (less than a day). If you do repost, add "repost" at the end of the subject. Quadruple posting within an hour and a half means that teachers have to spend time reading the extra posts, which actually slows ...


How do you determine the pH of a substance with an H+ concentration of 3.2 x 10^-3? Thanks in advance!


How do “chemical” salts form? Thank you in advance.


Repost .. Saccharin is a weak organic base with a Kb of 4.8X10^-3. A 0.672-g sample of saccharin dissolved in 30.0mL of water had a pH of 12.34. What is the molar mass of saccharin?

chem -repost for bobpursley

i don't know how to solve this. looked through all my notes but i'm not sure what kind of formula i am to use or if i even need one! please help me to understand the theory behind this: "calculate the work need to make room for the products in the combustion of S8(s) to SO2(g...


Was the airplane classified a social change or advance during the Roaring Twenties? I say that it was more an economic change or advance.


What is the hydrogen ion concentration, in mol dm−3, when 2.00 g of sulfuric acid is dissolved in water to give 0.400 dm3 of solution? could you explain in a simple and clear way please because im not very good at chemistry. thanks in advance


How do you factor 3x^2-x-4? thanks in advance How do you factor 3x^2-x-4? thanks in advance 3 times what = 3? 3 of course. giving you (3x+/-a)(1x+/-b). a and b can only be 1 and 4 or 2 and 2. Can you take it from here? (3x-4)(x+1)?

Science [improv/repost]

What is the difference between an ionic bond and a covalent bond? I just keep forgetting which one is which...any easy way to remember these? PS> I know that you're not supposed to repost until 24 hours but I really need this answer! Would this answer work?: In an ionic ...

Chemistry Lab

Do you expect acetaminophen to be soluble in 1.0 M NaOH? why or why not? thanks in advance

Chemistry Lab

Do you expect acetaminophen to be soluble in water? why or why not? thanks in advance


My question is that how can fe=fe(oh2)be balanced in a basic solution....THANKS IN ADVANCE.


24,8% of potassium ,34,77% of Mn,40,5% of oxygen how do i find the emperical formular thanks in advance


What does the reaction of alkaline earth metals with water tell you? Thanks in advance.

12th grade, Advance Algebra

How to press the value of log, to evaluate log, to find the unknown log using EL-531WH, advance D.A.L


tickets to a school play cost 1.5 in advance and 2.0 at gate. by selling all 200 tickets students got $360. how many tickets did they sell in advance?


Tickets to a show cost$10 in advance and $15 at the door. If 120 Tickets were sold for a total of $1390, how many of the tickets were bought in advance?


List the total number of each type of atoms in the following reactants. A) 2HCL + Ca(OH)2 = 6 hydrogen, 2 carbon, 2 lithium, 2 calsium, 4 oxygen B) 2Na3PO3 + 3Ca(NO3)2 This one is a bit more complicated. May any chemistry teacher show me how to do this. Thank you very much in ...

health information law and ethics

Advance directives are defined by your readings as written instructions recognized under state law, such as living wills or durable powers of attorney for health care, that relate to the kind of health care the patient wishes to have or not have when incapacitated. Also know ...

corrected repost chemistry

to what volume should you dilute 125mL of an 8.00M CuCl2 solution so that 50.0mL of the diluted solution contains 5.9g CuCl2 I have a hard time determing the M1V1=M2V2 is


Thank you Advance...;; Q: A body of mass 10 kg is moving over a smooth surface, whose equation of motion is given by the relation. s = 5t + 2t² where (s) is in metres and (t) in seconds. Find the magnitude of force responsible for the motion. Thank you Advance...;;


What is the pH of a 0.40 mol L^-1 H2Se solution that has the stepwise dissociation constants Ka1 = 1.3 × 10^-4 and Ka2 = 1.0 x 10^-11 ? Thanks in advance

organic chemistry

What does delocalization mean? what is the difference between non delocalizabe and delocalizable? Thank you in advance..

Pre-Algebra [repost]

I'm sorry I had to repost, but this is urgent and i need it done by today!! Can someone please show me how to do these problems? I've been trying but I'm having a hard time... 1.Simplify the expressions on each side of the equation to obtain an equivalent equation: 5x + 12 + ...

Chemistry-Repost for DrBob222

My question was: A saturated solution of MgF2 at 23 degrees C was prepared by dissolving solid MgF2 in 1 L water. The Ksp of MgF2 is 1.5e-5. a.)Calculate the mass of MgF2 dissolved. b.) When .1 mols of solid KF was dissolved in the MgF2 solution, precipitation was observed. ...


The program plans to acquire a total of 600 end items costing $570 million over a five-year period. The first production contract is to be awarded in FY04. The number of items to be procured (not delivered) each year and their estimated cost (in then-year dollars) is shown ...

Repost Repost Bio

I asked this, and didn't get a very helpful response. Question: hi, i did this lab, from this website and I was wondering if anyone could come up with 3 sources of error, and they can't be human error. Thanks! You are saving me! Seeing as I am not allowed to post to the ...


Hi, i was wondering if anyone could tell me the name for the compound with the chemical formula of Ca(H2ASo4)2 ? im stuck on this question. thanks in advance.


How do I draw a Born-Haber Cycle for diphosphorous pentasulfide? Formula: P2S5, but you knew that! Thanks in advance!

chemistry repost!!

The mole fraction of acetic acid (CH3COOH) in an aqueous solution is 0.675. Calculate the molarity of the acetic acid, if the density of the solution is 1.0266 g mL-1.

Fundamentals of Business Financial Management

Your program plans to acquire a total of 600 end items costing $570 million over a five-year period. The first production contract is to be awarded in FY04. The number of items to be procured (not delivered) each year and their estimated cost (in then-year dollars) is shown ...


a $200 cash advance by using checks linked to to her credit card account.The bank charges a 2 % cash advance fee on the amount borrowed and offers no grace period on cah advances.Sidney paid the balance in full when the bill arrived.What was the cash advance fee? What was the ...


How would I determine when isomeric dimethylbenzene yields 1 ,2 or 3 mononitro derivatives when treate with HNO3/H2SO4 Thanks in advance


Complete and balance the following equation S(s)+HNO3(aq)--->H2SO3(aq)+N2O(g) An explanation would be excellent, thanks in advance.


How would I balance the following redox equation? I know the Charge on the Br is 5, but i am comfused on where to go from there. H20 + Br^- + Al^3+ -> Al + BrO3^- + H^+ Thank you so much in advance

Chemistry repost

A student determined that ethanol was the best solvent to use for a recrystallization based on small scale trials. When the recrystallization was carried out on a larger scale, no crystals were obtained on cooling the hot solution. Why? and how would you overcome this problem???

chemistry lab repost

i need help locating a lab for regents chemistry. i have the data sheet but misplaced the rest of the lab. i know it's online somewhere, but i'm not sure which lab it is.. (what it is called). The data sheet has 3 charts on it, 1 titled 'solubility'. it includes water, alcohol...

chemistry repost

What is the boiling point of an aqueous solution that freezes at -6.7 degress C. Please help. I feel retarded because it seems like its something real easy but Im still not getting it. I did 100 + 6.7 and got 100.67 and are you sayin to divide 1.86 by .52 which is 3.576. the ...


acetic acid + copper CH3COOH + Cu -> CuCH3COOH? hyrdrogen peroxide (catalyzed by manganese dioxide) H2)2 -(MnO2)> H2 + O2? thanks in advance


Which of the following ions can be reduced from an aqueous solution? A)Ba2+ B)Al3+ C)Sn2+ D)Na+ Do I look for the higher volts? Thanks in advance.


Estimate the value of the equilibrium constant at 550 K for each of the following reactions. 1) 2CO(g) + O2(g) <==> 2CO2(g) 2) 2H2S(g) <==> 2H2(g) + S2(g) Thanks in advance!


Please tell me where I can find articles about polymers synthesis, I need one for presentation. Thank you so much in advance

Just a repost, in case the old isnt seen

sorry! I never noticed..the mass should be 52000kg sorry about that! For Further Reading physics repost - Alexis, Sunday, October 14, 2007 at 6:07pm so it should be a 52000kg train slows from 25 m/s to 14m/s in 5.0 s. Calculate the work done on the train. so I found the ...

chemistry repost

help, i'd like to know how to do this titration question: for example: a 1g sample of naoh contaminated with na2co3 is titrated with 0.500MHCl, and it is found that 46.5mL of HCl are required for neutralization. Find the percentage by mass Na2Co3. ( i did not make up these ...


Can someone explain to me, what does Metastable isotope means? I already read the definitions on the internet but I really don't understand it. Thanks in advance.

My algebra repost


math (repost)

y =x+2 y =x^2

college maths

on an annual renewal lease, the quarterly lease payment on office space is $1600 payable in advance. what equivalent yearly payment made in advance would satisfy the lease if the interest is 6.5% compounded quaterly?


Ermms just cant get my head around this question kinda bugging me :( Solid Sodium Hydrogen Carbonate dissolving in water i know its a dissociation reaction but i don't really have an idea where to split the compound. sorry about the repost, im new to this site and i aint ...


I have 25 million gallons of water at a pH of 6.5. I add 17.4 million gallons of 12.5% by wt sodium hypochlorite (NaClO) at a pH of 12.5 to this water. What will my pH of my final solution be? It's been about 5 years since I took chemistry and I just don't remember how to even...


Hi i am having trouble with this question: Name five household products that are not reactive, and for each product, describe the properties that make it ueful. Thanks in advance.


Why should the sodium hydroxide pellets be completely dissolved in the preparation of the NaOH solution? please explain thouroughly, thanksss in advance!!


0.560g of potassium hydroxide is added to 25.0 cm^3 of 1.00 mol dm^-3 of hydrochloric acid.Find the limiting reagent & please show the working.THANKS IN ADVANCE.


When 155 mL of water at 26 degrees Celsius is mixed with 75 mL of water at 95 degrees Celsius, what is the final temperature of the mixture? (d Water = 1.00 g/mL) Im really stuck on this problem and chemistry isnt exactly my strong point, thanks in advance!

research writing

Did Christensen use any counterarguments in his article in AIDS in Africa: Dying by the numbers. yes he did use counterarguments. Were they need to advance his thesis? yes it was needed to advance his thesis. What do you think of my answers. please do give feedback on them


Can Someone describe the structure of ionic compounds for me please.. Ionic compounds consist of a three dimensional array network of + and - ions. I expect you already know that. As to structure, here is a web site that may help. Repost if you have additional questions but ...


How would you prepare the ff. solutions: 1. 45g NaCl/g H2O 2. 25% w/v NaCl Thank you in advance.

About Posting

sorry for repost ~C


In adsorption, what is bulk concentration? How does that differ from initial concentration? Thanks in advance.

Chemistry (repost)

Pb(s) + KNO3(aq) ----> No reaction HNO3(aq) + Sr(OH)2(aq) ----> H2O + Sr(NO3)2 NO3 being Nitrate, and (OH)2 meaning 2 Oxygen and 2 Hydrogen atoms in the second problem. The second two in the products of the second problem is a subscript for NO3. Are these correct? Thank ...

Dimension Personal Education

Select the sentence that does not have a pronoun-antecedent error. 1. If anybody wants to go to that new restaurant, she or he has to make reservations a month in advance. 2. If anybody wants to go to that new restaurant, they have to make reservations a month in advance. My ...


Which of the following elements would have the largest third ionization energy: K, Ca, Ga? What is third? Thanks in advance.


does oxyanion contain oxygen? I think it contains oxide, but I'm not sure about oxygen. Thanks in advance!

Organic chemistry

How many nodes are in the pi* orbital of a carbon-carbon double bond? Please explain. Thanks in advance.


How do the qualities of acids and bases shape the natural world we live in? I really apppreciate, in advance, any help you can give me-I'm homeschooled and just trying to understand this better. Thank you-


What is the (simplified) meaning of Zn(s) + 2MnO2(s) ZnO(s) + Mn2O3(s) [e° = 1.43 V]? Please answer soon, because I will not be in class too much longer and I have no internet access at home. Thank you in advance!


What is the acid dissociation constant for a 0.010 M solution of the unkown acid HX that has a pH of 2.70 at equilibrium? I know the answer but not how to get it, please help? Thanks in advance.


What is a Reaction that you would expect when acetylsalicylic acid (aspirin) is heated in the presence of a CONCENTRATED acid? Thanks in advance!

Organic Chemistry

Is eutectic point and eutectic mixture the same thing? If not what is the difference between the two? Thanks in advance.

math (repost)

if f(x)=2x-1 and g(x) 1/2 (x+2) calculate a)f(3) now if 2(3)-1=5 how do i find for gf(3)????


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