# Chemistry (repost)

57,859 results

**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

**english**

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 ...

**history**

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

**chemistry [repost]**

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

**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.

**Chemistry**

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

**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 ...

**CHEMISTRY REPOST**

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!!!

**Chemistry**

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

**Science**

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

**algerba!2!**

(-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 ...

**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 ...

**Chemistry**

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...

**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 -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.

**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

**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 + ...

**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 ...

**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.

**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 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 ...

**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 ...

**math (repost)**

y =x+2 y =x^2

**Chemistry**

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 ...

**Chemistry**

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 ...

**About Posting**

sorry for repost ~C

**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 ...

**Chemistry-Repost**

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 ...

**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)????

**algebra repost**

simplify radical sqrt a^10

**To Danii**

I cannot read your 11:55 post. Can you repost it here?

**english**

sorry i havent really used this site and im not sure how to repost my question instead of putting it as an answer to my question so heres the repost: I had to find embedded clauses I deplore the fact that bats have wings. --> bats have wings That Guinevere loves Lorian is ...

**Abby**

Please repost your question, I accidently deleted it.

**6TH GRADE MATH**

Repost perimeter is 30 and area 36

**algebra 117**

repost sorry about that (k^1/8)^-4 oer(k^7)^1/2

**math**

repost find unknown number in the equation 9/10 - x = 1/5

**Chemistry (repost)**

Determine the volume of 0.240 M KOH solution required to neutralize each of the following samples of sulfuric acid. The neutralization reaction is shown below. H2SO4(aq) + 2 KOH(aq)---> K2SO4(aq) + 2 H2O(l) a) 26 mL of 0.240 M H2SO4 b) 143 mL of 0.14 M H2SO4 for a I got ....

**science**

Can you direct me to a site(s) which can help with college chemistry and statistics? Here are a couple of good chemistry sites that pretty well cover the waterfront. I don't know any stat sites but if you will repost with the subject line of "math" I'm sure someone will help ...

**History opinion repost for Kate**

Is the Bayeux Tapestry an accurate source? Why or Why not?

**Math (repost)**

Given f(x) and g(x)=f^-1(x). If f(1)=4 and f'(1)=-3, then find g'(4). ...No idea where to start with this. Please help? Thanks much!

**Algebra(repost of one question)**

Bobpursley: 89. Solve for x in the equation: (6/7)x - 6 = -2 I got x=28/3

**Algebra (repost)**

Can you help me on this problem as well? (or anyone.) Solve each inequality and check your solution. h - > -7 4 (bumping)

**Chemistry-Repost for DrBob222**

The reaction OH- + NH4+ = H20 + NH3 is kinetically first order in both reactants' concentrations. The rate constant is 2e10 1/M s. If 50 ml of .01 M NaOH is mixed with 50 ml of .01 M NH4CL, find the time required for the OH- concentration to reach 1e-4 M. Your answer: It ...

**Repost 2 PLz Help**

6-y/y^2-2y-24=? *I don't get it at all!!! You need parentheses around portions of this thing so we know what the problem is.

**repost Calculus**

the length of the curve of intersection of the cylinder (4x^2) + y^2 = 4 and the plane x + y + z = 2 I'm so lost. Any help is appreciated!

**Algebra**

|a+2 3z+1 5m|+|3a 2z 5m|=|10 -14 80| |4k 0 3 | |2k 5 6| |10 5 9| I needed to repost this. This is a matrice and I am trying to find the values of the variables in each equation.

**Repost of history**

Why did the Soviet Union support Turkey in the Greco-Turkish War?

**ethnics help**

sorry to interrupt is someone available for help. Please repost with your question, and we will do our best to help. Thanks for asking.

**REPOST biochem**

i don't understand this why can carboxyl and phosphate groups act as acids? as in, what makes an acid?

**chemistry HMWK help....... REPOST**

you decide to have a BBQ in your backyard. you have 1Kg of pentane (C5H12) in the tank. What is the amount of carbon dioxide (in mass and mols) you will be contributing to the greenhouse gas effect by using up that 1Kg of pentane? plz.... need the answer with steps...thank you...

**chemistry(check my explanation)**

sorry to repost this question but i'm confused on this part The solubility of borax is directly proportional to temperature. Therefore, the sign of H is A. negative B. positive C. unknown with the given information like you said earlier, borax dissolves when heat is added, ...

**egg protection**

how can i protect an from a 6m fall and make it go 3m please look at your question. It makes no sense to us. Repost it

**Science - Repost for ?????**

which moon is the brightest from the surface of jupiter? this question is driving me BLOODY crazy 4 my homework!

**repost**

bobpursely, I posted at 709 from our previous dialogue, can you please help me again? Much appreciated!

**physics repost**

Calculate the force of gravatational attraction between two spheres of mass 10.1 kg and 45.4 kg that are 38.5 m apart. F = G(m1)(m2)/r^2 = 6.67 x 10^-11(10.1)(45.4)/38.5^2 = 2.06 x 10 ^-11 N

**To Happy --**

Please repost your math question -- and remove Ms. Sue's and my screen names from YOUR NAME'S space. Thanks. =)

**Grammar [Repost]**

Is this an adverb phrase? The tangy scent of barbeque drew us TOWARD THE LITTLE CAFE. Thanks -MC

**algebra repost**

Simplify each expression. Assume all variables represent nonzero real numbers. -40^0- 30^0

**AP Chemistry (repost)**

some reactions that are considered to be spontaneous at low temperatures will not proceed at a measurable rate or form any measurable quantity of products for several hours, days, or years. a. explain why this is. b. will the addition of a catalyst alter the value of delta "G...

**math**

2Tons=____oz Try the method DrWLS or I showed you. Then repost if you don't understand but tell us what you are having trouble with.

**English**

Bloom's taxonomy, anyone? (Yeah, it's a repost.) Anything found on the wiki or the first page of google I've tried.

**physics repost**

A 1.00-kg ball is attached to a string of 0.50 m and swung in a horizontal circle with a velocity of 2.00 m/s. Find the centripetal acceleration. ac=v^2/r = 2.00^2/.50 = 8.0 m/s^2

**To "Cutie..."**

Please choose a better "First Name" -- make sure it's not offensive in the least! Then repost your question. Thanks. =)

**MzLynn - auditory learning**

Your post has been removed. We'll be glad to help you if you repost it along with your attempts to answer the questions.

**Physical Science**

if you tear a piece of material in haft, how is the density affected? sorry i repost it, just the title

**ap chemistry**

oxidation- reduction reactions What about them. Here is a site that may help you or repost with a more specific question. http://members.aol.com/profchm/redox.html

**Pre Calculus Repost Please Help**

Can someone help me solve this problem: cos^2x + 5cosx - 2= 0 I am having some trouble finding x

**To Ray -- college**

I've removed your biotechnology post. Please repost it with your thoughts about completing it and specifically how you would like us to help you.

**math repost**

name two numbers with decimal hundredth that round to the same whole number but different tenths.

**French for Anonymous/E.G.**

If you go back before the "repost" I found the first post just now! There is an answer there. Sra (aka Mme)

**To Sha -- Child Development**

I've removed your lengthy post asking you to comment on a complex scenario. Please repost with your analysis of this situation. We'll be glad to help you then.

**Math(repost of #2 of last ?)**

Write XY(with line over it) as the sum of unit vectors for X(8,2,-9) and Y(-12,-1,10). There's an example just like this in my book but I really don't understand it.

**science-repost! please help**

Determine if the following substances are soluble (at room temperature, 1 atm) in water or in hexane (: grease and CS2 how do you know this

**Repost(Physics)**

A vehicle moves in a straight line with an acceleration of 2 km/h^2. By how much does the speed change each second? Answer in units of km/h. Plz help?

**Chemistry**

What are charateristic of a ionic bond and a chemical bond? Answered below for characteristics of ionic bonds. I don't understand characteristics of chemical bond since an ionic bond is a chemical bond. Perhaps you can rephrase your question. For my partial answer look on this...

**Science**

I don't noe ne thng about fluids. HELp..my test is in two days If you repost your question and spell the words right, I'll help you. lol pwnT

**Repost: Biology!**

What would be the consequences of the following be on photosynthesis? These are the only ones I am stuck on! a.) Photosystem I is not functional b.) NADP+ is not present in the thylakoid space

**physics repost**

Which of the following physical properties can be used to measure temperature using a thermometer? A)volume B)pressure C)density D)viscosity I got A

**True or False econ repost**

Relative PPP is a better approximation of reality when one of the two countries is suffering hyperinflation and the other is not.

**Pre-Algebra [repost for Reiny]**

In my last post for #1, I asked my teacher and she said that it's actually k=30 . Could you have gone wrong somewhere? That's the only one. -MC

**chemistry**

Does this equation need to be balanced? AlCO3 => AlO+CO2 Also, how would this equation be balanced? NiCl+O2 => Ni2O3+Cl2O5 Neither equation you have is an equation so they can't be balanced. Do you mean aluminum carbonate. That would have the formula Al2(CO3)2. Aluminum ...

**ap chemistry**

what does H2 + CH2 form? (what product?) What is CH2? There is a (CH)2 but I don't know of a CH2. Yes, I meant to ask: What product is formed by this reaction: H2 + (CH)2 My original answer is gone but I will repost. (CH)2 is HCtriplebondCH which is acetylene. H2 gas adds ...

**Chemistry-Repost**

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==...

**government**

describe a hypothetical situation in which collective naturalization might be applied? We do not do your homework for you. However, if you will repost your answer, we will be happy to proofread and give suggestions.

**To: Troyer0269 - Sci245**

I've removed both of your science posts. Please repost when you can tell us what you've done so far to fulfill these complex assignments and where you specifically need our help.

**To: Computer -- Cultural Diversity**

I've removed your post with the complex assigment about subordinate groups. Please repost it and tell us what you've already done on this assignment and how we can help you complete it.

**Algebra - Repost**

Hello, I am reposting with correct ASCII format with my answer: (4x^5y^6z)2^ X (5x^9y^12z)3^ (16x^7y^8z^2) X (125x^12y^15z3^) 2000x^19y^23z^5 Thank you

**Repost PLease Help!**

d+7/d^2+49= / (d+7) (d+7)*I got the bottom but I don't know what to put at the top...please help!!! answered below

**physics repost**

Calculate the sound level in decibels of a sound wave that has an intensity of 2.25 µW/m2. F

**Calculus - repost**

Find the derivative of F(x)= integral from -2 to x of sqrt(t^3+8)dt? My answer: sqrt(x^3+8)? Is this right?

**To JMartina**

Please do not post your e-mail address here. Repost your question, please.

**Repost physics**

PLEASE SOMEONE HELP ME!! I POSTED DOWN AT AROUND 10 something!! PLEASE!!! I NEED HELP!!!

**physics repost**

sorry! I never noticed..the mass should be 52000kg sorry about that!

**S.S. Repost for Brittani**

S.S. - Brittani, Friday, October 26, 2007 at 5:47pm Where are charges for the impeachment made?