Post a New Question

Chem (edited)

7,230 results

CHEM 101 (edited)
Calculate ΔHrxn for the following reaction: CaO(s)+CO2(g)→CaCO3(s) Use the following reactions and given ΔH values: Ca(s)+CO2(g)+1/2O2(g)→CaCO3(s), ΔH= -812.8 kJ 2Ca(s)+O2(g)→2CaO(s), ΔH= -1269.8 kJ I have literally tried everything and I don't understand what I am ...

Chem (edited)
The electrolyte from a car battery has H2S04 (aq) concentration of 4.5 per mol per litre and a density of 1.18g per ml What is the percentage by mass of H2S04 in the electrolyte? do you mean 4.5 mol per liter? This has absolutely no meaning: concentration of 4.5 per mol per litre

Grammar
My teacher edited my story and I do not understand the abbreviations that she used. Does anyone know what she means by SV and SA.

french - final draft
Well.. i posted this before and I re-edited a few things. I need suggestions and editing please :)

English
Is there a story in America Street, edited by Anne Mazer, similar to The Journey by Duane Big Eagle?

English
Hi, my teacher edited my paper and she said I need to pick a different transitional word rather than "next" or "then". Any suggestions?

@Miranda - statistics
Please re-post your edited statistics question.

English
I wanted to post my English thing here for it to be edited but not want it to stay public on internet, is there way to make it private ?

English
When should you use a modified outline? 1) when you need to record information quickly 2) when you’re organizing a formal essay 3) after you’ve edited your research paper I think it's number 2.

Java
Write a method that will take in a String parameter and return true if the first 2 chars in the string also appear at the end of the string, such as with the word "edited", which starts and ends with 'e' and 'd'.

access
Which one of the following statements accurately describes the AutoNumbers field in Access? A. Requires a mathematical calculation B. Includes the currency symbol C. Is automatically assigned as the primary key D. Can be edited with values from another table

English
I need intro paragraph proofread and edited please source used for intro paragraph : empire demands discipline, the coordination of all forces and a deeply felt sense of duty and sacrifice: this fact explains many aspects of the practical working of the regime, the character ...

finite math
According to a certain countries 44.5% of 3 year olds are enrolled in daycare. What is the probability that a randomly selected 3 year old is enrolled in daycare. edited

english
I have a book I need to cite that is a composition of works by the correspondents of the New York Times but it was edited by Bernard Gwertzman and Michael T. Kaufman. How do I do that? You'd simply name them and put Eds. after the second name. There would be no author named, ...

Please Help:-(
I really need someone to look at my previous posts and edit them if they need to be edited. Please point out any grammatical errors. Thank you very much. You will find my posts as soon as you enter my name in the Search Box.

English
For the essay I have to write I have to talk about examples of sequences and montages (which are transitional sequences of rapidly edited images) for the movie "The Gold Rush" by Charlie Chaplin. I'm having a hard time with examples of montages. Can you help please?

chem
what are the other practical applications of Analytcal chem on being a medical technologist?

chemistry
can you please give me some practical applications of qualitative chem and quantitative chem...

Algebra/Language Arts
I have a 15 page paper due tomorrow. I finished the paper, and edited it and all, that's not my problem. My cover page is a work of art that I designed and I wanted to put a note on how it relates to my essay. How would I go about doing this? Do I add a page at the back after ...

chem- drbob222 please help
my original question was: how do i figure this out?? How much heat does your body lose when 2.46 g of sweat evaporates from your skin at 25°C? chem - DrBob222, Tuesday, February 22, 2011 at 10:52pm q = mass water x delta Hvaporization. chem - Rebekah, Wednesday, February 23, ...

english-thesis
Heritage plays role x with regard to marriage in Howell’s novel, while in Larsen it plays role y, allowing the man to accept African American women in the former, but reject her in the latter. this was how my teacher edited it but he said something like :See how if you fill ...

chem
so i posted this question yesturday and got some help. which is the stuff below. can you look at the last thing i said which was the answer i got by doing what DrBob222 said to do and tell me if its correct.(the question is the first section) thanks chem - hannah, A salt ...

chem chem
hi does anyone know what the VSPER theory is

chem
if a car produces 81g of {\rm CO_2}, how many grams of {\rm O_2} are used up in the reaction? the complete chem reaction is C2H6O+3O2--->2CO2+3H2O

English
Please check. 1. A book published by Harcourt Press, Inc. It was published in 2001. Harcourt Press is located in the city of New York. The title of the book is Medieval Pageant, and the author is John R. Reinhard. Reinhard, John R. Medieval Pageant. New York City: Harcourt, ...

Chem Help!
I really need help with this question for my chem H.W. 1) On a summer day in Breckenridge, Colorado, the atmospheric pressure is 525 mm Hg. What is this air pressure in atmospheres? (round to the hundredths place) atm

Chem- bobpursley
What mass of protons would be required to just neutralize the charge of 1.5 g of electrons? my teacher said .0015kg times 1e-/.00091e-27kg times 1pt/1e- times 1.67262e-27 over 1 p chem - bobpursley, Tuesday, September 21, 2010 at 6:48pm That is what I would do also. But I ...

chem - br bob is this right
What is the pH of a solution prepared by adding 4.000 grams of NaOH to a 50.00 mL of a buffer that is 2.00 molar both in acetic acid and sodium acetate? (Assume final volume is still 50.00 mL) * chem - DrBob222, Wednesday, April 21, 2010 at 10:52pm * chem - phil, Wednesday, ...

Chem
What causes dispersion forces? Disperson forces are caused by an unsymettrical distribution of charge in the molecule, causing a net electric force. http://www.chem.purdue.edu/gchelp/liquids/disperse.html

Gen Chem II
Thanks for the information Dr. Bob. Would you be able to work it out so that I can actually see the steps with the numbers and follow from there. The question was on Vitamin K from Sunday at 2:44pm which you answered at 3:45pm. Thanks again. I am looking to get a tutor since I...

AP CHEM
A secondary alcohol results from the attachment of a hydroxy group to which carbon atom? C | <---GIVEN STRUCTURE C1-C2-C3-C4 A) C1 B) C2 C)C3 D)C4 Answer is C! I have to explain why, but the teacher never taught us anything about organic chem. So please explain!

English
Which sentence should be edited to eliminate its cliché? A. The texture of the burlap was a cross between woven straw and a three-day beard. B. The family was immensely relieved when Great-Aunt Martha's condition progressed from "critical" to "it looks like she'll live ...

English
Which sentence should be edited to eliminate its cliché? A. The texture of the burlap was a cross between woven straw and a three-day beard. B. The family was immensely relieved when Great-Aunt Martha's condition progressed from "critical" to "it looks like she'll live ...

Dr.Bob222 Chem
I believe that you are correct because you have more experience in G-chem then I have. But how does doubling the reaction rate double the k value? Isn't k just a constant for a particular reaction?

chem org
dipole-dipole means? and diff between non polar and polar? is it really part of organic chem?

Chem 1
Write a chemical equation that shows how acid rain H2SO3 was produced from SO2 gas and water in a zip sealed bag? My chem. teacher never explained how to do this and I have several other questions on this type of subject. If you could help me out it would help me tremendously...

physics vs. Chem
Doesnt physics seem to be harder than chem? Anyone?

Advice...about chemistry degree Dr.Bob
Based on the question topic posted by Britney below titled:In your opinion (your answer to this reminded me of something) (I posted the same thing there but I thought it was improper to piggyback on that post so I posted this under a new topic) I don't know where to start but ...

Edited questionSCIENCE
Speeds up or slows down? By stirring a gas in a liquid, its solubility ____________ the dissolving process. High or low? A gas's solubility is is faster in a liqud when under __________ pressure. How do the methods of speeding the rate of solution for dissolving a solid in a ...

Media- help with a reference
I'm currently writing an essay for university but have a slight problem with one of my references. The source comes from a book called Screen Violence which is a collection of essays, edited by Karl French. The piece that I am referencing from is an 'Interview with Karl French...

sra JmcGuin spanish
assignment como va a ser nuestro mundo dentro de 50 anos? Piensa en el medio ambiente, el sistema social, la religion, la education, el transporte publico, la tecnologia...usa si + prente + futuro por lo menos 3 veces. THE ABOVE DOES NOT NEED TO BE EDITED IT IS THE ASSIGNMENT ...

sra JmcGuin spanish
assignment como va a ser nuestro mundo dentro de 50 anos? Piensa en el medio ambiente, el sistema social, la religion, la education, el transporte publico, la tecnologia...usa si + prente + futuro por lo menos 3 veces. THE ABOVE DOES NOT NEED TO BE EDITED IT IS THE ASSIGNMENT ...

sand bath (chem)
what are disadvantages and advantages of using a sand bath to heat something in chem?

chem
What is another name for cardamist? Please write the formula and a link to its structure. See http://antoine.frostburg.edu/chem/senese/101/consumer/faq/what-is-cardamist.shtml

Chem - DrBob222 & drwls
Just want to say thanks to you guys for the help you gave me during the last couple of months. It was all in preparation for the National Chemistry Test and I just received word I have been selected to be in the running for the National Chem Team. Thanks again.

CHEM organic chem
i am really confused! i am doing the production of ethene from fractional distillation and i understand the whole concept of it what i don't get is how i can write a balanced eqn to show how ethene can be produced from C14H30 (tetradecane?!) i did C14H30 ------> C7H14 + ...

CHEM organic chem
i am really confused! i am doing the production of ethene from fractional distillation and i understand the whole concept of it what i don't get is how i can write a balanced eqn to show how ethene can be produced from C14H30 (tetradecane?!) i did C14H30 ------> C7H14 + ...

chem equations
could someone tell me how i could solve this chem equation CH4 + NH3 +O2...> HCN +H20 AND USE THE LOWEST WHOLE NUMBER COEFFICIENT i WOULD BE GRATEFUL FOR ANY POINTERS Try these coefficients. 2,2,3==>2,6 Hi bex heres a little more help for you. Answer is 2CH4+2NH3+3O2--&...

Chem
Are: Ba(NO3)2, Ti)2, MgI2, and Ca(CH3COO)2 soluble or insoluble in H2O @ 25degrees C? Here is a site that lists the solubility rules. You should know this table; eventually you will want to know it so well that it is memorized. If you still have questions after viewing this ...

English Essay Advice
My college professor is a highly difficult grader and will always find a way to take her students' papers apart. Therefore, any advice regarding the following essay topic would be appreciated: How has YouTube altered our definition of creativity? (We are also supposed to use ...

chem help
im doing a graph for chem lab with excel. my classmate created a graph with these coordinates: X: 3.50 X10^-3 3.14X10^-3 3.28X10^-3 Y: -11.7 -8.96 -9.75 They got R2=0.998 but i got y = -3074.9x R² = 0.6291 why is it wrong. im desperate please help! screen shot of my graph: ...

Chemistry
Ok, so in my gen chem 1 class, the teacher showed us that ethanol would not dissolve a sugar cube while water dissolves a sugar cube easily. No explanation was given, she just told us we would find out in gen chem 2. Here i am in gen chem 2, and the same thing is shown to us ...

chem/science
Please predict what will happen. Im not very good in chem. Iron metal and pb(NO3) Lead metal and Mg(9NO3)2 Copper metal and AL(NO3)3 Lead metal and AgNO3

Chem
A 10.0% by mass H2SO4(aq) solution has a density of 1.07 g·cm-3. How many milliliters of solution contain 8.34 g of H2SO4? What mass (in grams) of H2SO4 is in 248 mL of solution? It's been a while since I have had a chem class...so sorry if this seems really easy I just don't...

Chem
Calculate the expected volume of hot water that would be required to dissolve 0.15g of benzoic acid, vanillin, phthalic acid, salicyclic acid? You don't need to do all or any of them. I just need to know what formula to use and what to sub in and I can do the rest myself. I ...

organic chemistry
whats the difference between inorganic chem and organic chem? im really confuse because mrs. white told us inoraganic is about ionic bonds while organic is about covalent bond. what is the difference between the twooo? please help me

I have a question concerning Spring Semester
Im a freshman in college and I just took Chem1, Trig, and Drama (12units). I am planning on taking Chem2, Pre-Calc, and Art1 for spring sem. (13units). I'm not sure if this is too much to take for next semester considering two five unit classes or should I add another class? ...

English
This is a paragraph for my essay about how immagination influenced Macbeth to commit murders I need it edited and proofread plz: Throughout the play Macbeth by William Shakespeare, imagination influenced Macbeth to do evil in hopes of achieving his goal. An example of how ...

Math
*Edited* (thanks Alex!) In a class, 4/5 of the girls have brown hair. Of the brown-haired girls, 3/4 of the have long hair. Of the girls with long brown hair, 1/3 of them have green eyes. Question: What fraction of the girls in the class have long brown hair?

Gen Chem
For my chem class I have 3 elements and have to find what they are used for today or an interesting fact. I have looked but I can't really fin anything. My elements are: Cobalt,Thulium, and Roentgenium I found that cobalt is used in money (nickels, quarters, and dimes, but ...

High school AP chem
The solubility of Mn(OH)2 is 3.04 x 10^-4 gram per 100 ml of solution . A) write the balanced chem equation for Mn(OH)2 in aqueous solution B) calculate the molar solubility of Mn(OH)2 at 25 degrees celcius C) calculate the value of the solubility product constant, Ksp, for Mn...

Chem
The solubility of Mn(OH)2 is 3.04 x 10^-4 gram per 100 ml of solution . A) write the balanced chem equation for Mn(OH)2 in aqueous solution B) calculate the molar solubility of Mn(OH)2 at 25 degrees celcius C) calculate the value of the solubility product constant, Ksp, for Mn...

English
Need paragraph edited The influence of imagination also occurs in everyday life. An example of how the influence of imagination leads to a positive outcome is Michael Jordan becoming a famous basketball player. At a young age Michael Jordan dreamed about becoming a basketball ...

Final-Chemistry
I have finals coming up in a week and a half. I know I should have started studying earlier, but I just had an exam in my chem class and was focused on getting the information for that exam mastered before I started studying for the final. Now, I'm overwhelmed. I have no idea ...

General Chem
So for Chem we have to answer a question asking why graphing is a more accurate method for measuring density than manually calculating the density. I originally thought that manually calculating was better, but my teacher told me that I would have to back that up with a lot of...

drying agent in chem
Is it advisable or not to leave a solution in drying agent for a few days? ~I did this ..since my chem lab instructor said to but I'm not sure I believe him. He sounded unsure of himself when he answered me. solution: methylene chloride (extracting oil of caraway) drying agent...

history
Use the excerpt to answer the following question: "And so as it were at the same moment the master's command is given and the disciple's work is completed, the two things being speedily accomplished together in the swiftness of the fear of God by those who are moved with the ...

Math
in a class of 60 students 30 like maths 25 like physics 30 like chemistry. if 10 like both physics and maths 5 like maths and chem and 5 like phy & chem and 3 like all the subjects. find student like none of subject of if 100 students were surveyed

Math
in a class of 60 students 30 like maths 25 like physics 30 like chemistry. if 10 like both physics and maths 5 like maths and chem and 5 like phy & chem and 3 like all the subjects. find student like none of subject if 100 students were surveyed

chem
Ionic bonds and covalent bonds, which one is the stronger. My present teacher said that covalent bond is the strongest one. I learned ionic interaction is the strongest and many chem. books say so. Now i am confused. Is my present teacher right. Please explain this for me, and...

chem HELP PLEASE its physics side of chem
given E, = l^2 h^2 / 2 m r^2 calculate energies for an electron localised to a circle of radius 2 x 10^-9 m for l = 0,1,2, draw pictures of three levels and calculate the relative populations of these levels at 300K i did the first bit but came out with, 0, 6.0249 x 10-6 J mol...

chem-> front page report
wondering if this looks good or should I make the format some other way. Multistep Synthesis of 4-Bromo-2-Chloro-6-Iodoaniline name school Chem###sec## Multistep A,B March 13,2008 Multistep C March 20,2008 Multistep D March 27, 2008 Multistep E April 03, 2008 not sure if I ...

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...

CHEM (DrBob222)
I had posted the question to that previous chem question, regarding Mo & V...they said that it should have been correct. What I am thinking that I was missing...must have been that I did not include 4s & then just not fill it. I had excluded it from my electron filling ...

Chemistry
Are propane, methoxymethane, and ethanol soluble in water? yes http://www.chem.lsu.edu/lucid/tutorials/solubility/Solubility.html Henry is wrong.

CHEM 2: Boiling Point
Which Aqueous solution has the highest normal boiling point? a.) 0.1 m NaCl b.) 0.1 m C2H5OH c.) 0.1 m CaCl2 d.) They all have the same boiling point. I think that the answer is D, the all have the same boiling point. Is this correct? Because Delta T= K(b)msolute .... and if ...

mass media
what are pre-book manuscripts and what is the early publishing houses? Pre-book manuscripts are the hand-written or typed (word-processed) pages of an author's books before it's been edited by the publisher. Check these sites for early publishing history. http://www.infoplease...

AP Exams?
I am in AP Chemistry and AP U.S Hisotry and I have planned on taking the tests. So far I have made an A+ in APUSH, but I an B in AP Chem. I've done kinda bad on the tests I've taken in there and I don't think I will do good on the Ap exam. I think I have a better chance at ...

English
i need the body paragraph below edited and proofread please, i am trying to prove that empires are wrong. Some people believe that the building of empire provides a secure natural resource due to taking over territories owned by other countries. This ultranatilsm can actual ...

Literature Essay (Ms. Sue and/or Writeacher)
This is a edited version of my first body paragraph. "I feel as though there is a far greater number of people today who are more fearful than those of past generations due to many different reasons. Such reasons can be drawn from any source of this present day, such as daily ...

english
1. Which of the following sources is least likely to have been edited for accuracy? (1 point) a city newspaper a personal Web site an encyclopedia article a published book 2. Which of the following is NOT true about bias? (1 point) Using both biased and non-biased resources in...

chemistry
Why must a calculated answear generally be rounded? and how many siginificant figures must you round an answear to when performing multiplication or division? http://chemed.chem.purdue.edu/genchem/topicreview/bp/ch1/sigfigs.html

Chem
The correction terms in the Van der Waals equation for a gas are designed to correct A. the pressure term (P +a/V2) for the attractive forces between particles. B. the volume term (V-b) for the finite volume of the particles. C. For the volume term (b) not the pressure term (a...

chem lab
hi im doing a post lab sheet for chem class. and im having a little trouble. i have: temperature 12.6 C -> 285.6 K Time 816 sec but im supposed to find 1/T(K) it looks like my classmate did this: 12.6 x 285.6 = 3598.56 however they gave me the response to group 2 also: and ...

English
Could you please check these sentences for me? Can you help me express the following ideas better? Thank you. 1) If you don't get a "passed" out of your last written test you'll have to take a make-up exam in English August (to make up for your low mark in English). 2) I'm ...

Science
What is the structural formulae for the equation for the hydrolysis of lactose? It is impossible for us to draw structures on the computer. Here is a web site that may help you. http://www.rpi.edu/dept/chem-eng/Biotech-Environ/IMMOB/lactose.html

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 ...

Chem
C2

science(chem)
Concerning TLC plates... 1. why should't I allow the solvent to reach the top of the plate? (I assume it's the same as using paper like I did in gen chem but I'm not sure I know why it shouldn't be allowed to reach the top... what would happen?) 2. why sholdn't the spot sample...

chem
what is the % of CI in CCl4?

chem
Br + CHCOOH

chem
H2 + H2O ->??

chem
what does S.T.P mean?

chem
i need help

chem
What is the pH of 0.2 M HN3?

chem
2.0 x 10(exp-13) km/0.01=

chem
6.46g

confused creative writing
In creative nonfiction, a quote is differentiated from fictional dialogue in that it: takes the liberty of re-creating someone's spoken or written words is closer to the truth than fiction dialogue can be edited to change the piece's emotional impact copies someone's actually-...

science
which of the following could not be reduced to a simpler piece of matter? compound, solution, element, mechanical mixture? Your exact answer is at the following site: http://www.syvum.com/cgi/online/serve.cgi/squizzes/chem/elements_compounds_mixtures.html

another chem question
Examine the following unbalanced chemical equation: CO(little2) + C --> CO Which of the following is the correctly balanced form of this equation? 2CO(little2) + C --> CO CO(little2) + C -->2CO CO(little2) + C(little2) --> CO CO(little2) + C -->C(little2)O ...

  1. Pages:
  2. 1
  3. 2
  4. 3
  5. 4
  6. 5
  7. 6
  8. 7
  9. 8
  10. 9
  11. 10
  12. 11
  13. 12
  14. 13
  15. 14
  16. 15
  17. Next>>

Post a New Question