# chemistry! URGENT

59,905 results, page 23

### Chemistry

Look up the solubility of NaCl in both water and ethanol (in the CRC handbook of chemistry which i don't have access to, and any help would be appreciated) Consider the dissolution process, and competing intermolecular forces to account for the observed differences in solubility.

### Chemistry

what volume of ammonia gas will be produced when 1.26L of nitrogen react completely in the following equation? N2 + 3H2 > 2NH3 Please if someone can just give me the order of operation it will be much appreciated because chemistry is just not my forte.

### chemistry

A 1.00L sample of a gas has a mass of 1.92g at STP. What is the molar mass of the gas? (This is a question on my chemistry worksheet, and I can't find the answer in my book.)

### chemistry

The actual chemistry question was, given that there are 4.19 g of C6H6 how many moles do you have and this is how I solved it and it was wrong. 4.19g/78g/mole = .054 moles of C6H6

### maths

in a class of 35 students twice as many study chemistry and study physics half a many study chemistry as study both subjects illustrate it on a venn diagram

### Chemistry

The chemistry problem is "How would you make 500.0 mL of a 3.00 M HCl solution form a stock solution that is 6.00 M?" I have no clue how to even approach this problem.

### Chemistry

From the Standard Potential Table in your general chemistry textbook: Which reaction has been chosen as the 'standard' against which every other reaction is measured? A. 2H+ + 2e– ==> H2 B. O2 + 4H+ + 4e– ==> 2H2O C. F2 + 2e– ==> 2F– D. Li+ + e– ==> Li E...

### chemistry

hi Dr Bob..can you please help me with this chemistry problem? I got problem dealing with the chemical formula.How i want to find the number of moles of 2g of Fe(NH4)2(SO4)2.6H2O???please help me.Thank you

### chemistry

A student is asked to prepare 250.0 mL of 3.5 M copper (II) sulfate from solid copper (II) sulfate pentahydrate. Describe how this solution should be made in the chemistry laboratory.

### chemistry

A chemistry experiment needed 12.45 grams of chemical to produce one liter of a gas. If Zoe wanted 24 liters of gas, how many kilograms of the chemical will she need?

### Chemistry

I have a gr 10 chemistry unit test coming up can someone please refresh my mind on this unit? and tell me what things i should practice for the test? Tyy

### Chemistry

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 ...

### Algebra 1- Urgent

The price of products may increase due to inflation and decrease due to depreciation. Derek is studying the change in the price of two products, A and B, over time. The price f(x), in dollars, of product A after x years is represented by the function below: f(x) = 0.69(1.03)x ...

### Macroeconomics

A bank has \$200 reserves, \$800 loans, \$400 securities, \$1200 deposits, and \$100 debt. a) Calculate the bank's capital. b) Calculate the bank's leverage ratio. c) Suppose there is a stock market boom, so that the bank's assets increase by 2 percent. What is the percentage ...

### honors chemistry- isotopes...

can scientists actually measure the mass and relative abundance of isotopes of an element by counting each particle and measuring their masses? [ i think no because it would be too small ] if not, how could a scientist measure the mass and relative abundance of isotopes of an ...

### Chemistry

Why are numbers used in chemistry often expressed in scientific notation? They otten are very large or very small. Printing those types of numbers is onerous.

### Chemistry

In chemistry, how is a monomer related to a polymer? Think of a chain: Each link is a monometer, as the links are joined, you have a chain which represents the polymer.

### Chemistry/pH- Weak Acid

in response to Chemistry/pH- Weak Acid. but the rule of 5%? 0,0100/(1.00x10^-4) =100% The aproximation you do is not valid...or? Ka= (1,0*10^(-4))^2/(x-1*10^(-4) )=1,00*10^(-6)....I got c=0,0101M :-(

### chemistry, organic chemistry

How do we calculate the temperature of a mixture of hexane and heptane at which the mixture solution equals 1atm?This will be the boiling point of the solution

### Macro check and help

A bank has \$200 reserves, \$800 loans, \$400 securities, \$1200 deposits, and \$100 debt. a) Calculate the bank's capital. b) Calculate the bank's leverage ratio. c) Suppose there is a stock market boom, so that the bank's assets increase by 2 percent. What is the percentage ...

### Urgent physics help

1. A runner starts at rest and accelerates uniformly at a rate of 0.85 m/s2 . What is the runner’s velocity after the runner has traveled 6.0 m? A. 2.3 m/s B. 3.2 m/s C. 5.1 m/s D. 10.2 m/s 2. An official drag race in the United States is usually 1/4 mile long, which is 402 ...

Sorry to repost this, again, but I still don't understand. Newton’s Law of Gravity specifies the magnitude of the interaction force between two point masses, m1 and m2, separated by the distance r as F(r) = Gm1m2/r^2. The gravitational constant G can be determined by ...

### Math

Lee has two tests to study for: Chemistry and French. She plans to study for up to 13h in total. She will spend at least 4 hours studying Chemistry and up to 6 hours studying French. Let x represent the number of hours she will spend studying Chemistry, and y the number of ...

From the Standard Potential Table in your general chemistry textbook: Which reaction has been chosen as the 'standard' against which every other reaction is measured? A. 2H+ + 2e–H2 B. Li+ + e–Li C. O2 + 4H+ + 4e–2H2O D. F2 + 2e–2F– E. H2 + 2e–2H– is it A

### Physics Urgent!

Please help! This is due in three hours and I don't know how to do these! 1.A block accelerates at 3.1 m/s2 down a plane inclined at an angle 24.0◦. Find μk between the block and the inclined plane. The acceleration of gravity is 9.81 m/s2 . 2.Two blocks connected by a ...

### Chemistry

A chemistry lab experiment requires 34.0 g of silver nitrate. How many grams of a 23.1% by mass solution of silver nitrate should be used?

help me out in choosing a topic for my project it should be anyhow related to chemistry help me please

### Chemistry

I was given extra credit to find who Le Châtelier's High School Principal was. Not his PrincipLE, but his PrincipAL. My chemistry teacher told us only one student of his out of all these years came with the answer. Think outside of the box. Thanks.

### Chemistry

I was given extra credit to find who Le Châtelier's High School Principal was. Not his PrincipLE, but his PrincipAL. My chemistry teacher told us only one student of his out of all these years came with the answer. Think outside of the box. Thanks.

### Chemistry

I have a question in chemistry about combining compounds. I didn't really understand from my teacher. I have to combine Pb(NO3)2 with Na4OH. Also combine CaCl2 with Na2SO4. Can someone explain.

### Experimental Chemistry

(Experiments in synthetic chemistry) For heating under reflux, must the solvent level in the round bottomed flask be above the oil level (in the hot oil bath)? Why? Thanks.

### Chemistry

Can someone please help me solve this homework problem for my chemistry class.It's my last problem and I'm stuck!:/ Thanks :) A 4.0*10^1kg sample of water absorbs 308KJ of heat. If the water was initially at 25.5 C, what is its final temperature?

### urgent

hey you guys I post a question like five hours ago and I would like to know if there is at least a website in were I could get help or something Post your question again. That way it'll get to the top of the list. That's what I always do. Your original post listed several ...

(imageshack)(.)us(/)photo (/) my-images (/)42(/)2vja. jpg(/) Open that link please , just delete the parentheses please please help me with my assignments I beg you cooperate with me huhu 1. in the figure , the areas of traingle cef, triangle abe, triangle adf are 3,4, and 5 ...

### Math-Urgent

A circus performer is juggling clubs while standing on stilts. He released a club from a point 8 feet above the ground with an initial vertical velocity of 10 ft per second. a. Write the equation that models the height [h] (in feet) of the club as a function of the time [t] in...

### English

What are some words to describe the tone of an author's diction? This list comes that an AP English teacher in Raleigh, NC gave her students. TONE WORDS: angry, sharp, upset, silly boring, afraid, happy, hollow, joyful, sad, cold, urgent, joking, poignant, detached, confused, ...

### Chemistry

I keep reading that lead is a poor electrical conductor, but I would like to know the chemistry of why exactly it is a poor conductor.

### French (URGENT)

Okay, for an assignment, I have to interview my partner in French. So I wrote down the questions I would ask him in English, but I don't know enough French to translate them. Can someone please help me translate these sentences into French? What is your name? Comment t'...

### Chemistry

I did a lab in chemistry about weighing table salt and sand and mixing it with water and pouring it through a funnel. One of my lab quetions was, What are some possible sources of error in this activity? First of all, I don't know what this question means. Can anyone please ...

### Chemistry

Although I do very well in chemistry I never really understood converting units. Perform each of the following conversions. A. 8.43cm to millimeters B. 2.41x10^2cm to meters C. 294.5nm to cm D. 1.445x10^4m to kilometers E. 235.3m to millimeters F. 903.3nm to micrometers

1) The Ka for acetic acid is 1.8e-5. What is the pH of a 3.18M solution of this acid? I did 1.8e-5 = x^2/3.18 x=sqrt 1.8e-5 X 3.18 = 7.56e-3 pH=-log(7.56e-3) = 2.12 The pH is 2.12 2) At 25 degrees celsius, the pH of a 1.75M NaCN solution (the Ka for HCN is 4.0e-10) is ? 4.0e-...

### 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.

### General Chemistry

The four quantum numbers for the last electron placed in the orbitals of a certain element are: n=3 l=2 m of l=0 and m of s=-1/2. What is the element? I need help with this part of chemistry I have NEVER understood this ever. I know how to do the configurations but not this. I...

### Socials Studies (URGENT) #2

Alright, for my children's story on life in New France. This is what I have so far. --------------------------------------- Little Jon-Jon was exploring his backyard. He saw a tunnel that wasn't there before. He crawled right in.... ...and came out the other side. He was in a ...

### English

Can you please check the following sentences? It is really urgent. Thank you very much. 1) Last summer I went to South Africa with my family. In my opinion, it was the most exciting holiday I have ever had. 2) Actually, South Africa has got a lot of wild animals such as lions...

### Biology URGENT!!!!

What are five characteristics that scientists use to group dissimilar organisms into common groups? List references too please. Thank you. http://faculty.fmcc.suny.edu/mcdarby/Majors101Book/Chapter_02-A_Bit_of_History/02-Explaining-Life-Classification.htm http://www.uoregon....

### Urgent! PLZZ HHEELLPP!!

8. Which answer best describes a main benefit of the Transcontinental Railroad? A.) It proved to the world that the United States was capable of great feats of engineering B.) It created safe, high-paying jobs for immigrants who wanted to work building the railroad C.) It ...

See question below at **** Suppose local govt decides that a tax is the best way to address the inefficiency created by outdoor concerts. Assuming the social cost curve and the private cost curve are parallel to each other, how much does the tax on concerts have to be to ...

### chemistry

A chemistry student weighs out 0.0294g of sulfurous acid H2SO3 , a diprotic acid, into a 250.mL volumetric flask and dilutes to the mark with distilled water. He plans to titrate the acid with 0.2000M NaOH solution.

### Geography - URGENT!

It has been said that Eastern Europe is a political region more than a physical region. Would you agree or disagree with this statement? You must provide a solid argument for your position. My answer: Eastern Europe has only been a political region since after World War II. ...

### urgent!!!words questions

I have alot of questions here but you don't have to answer them all but please help me!They are due on 24/6/05. The male of mare? The citizens of Paris,Netherlands,New Zealand or Malta? The collection name for cattle,wolves,lions,elephants or whales? What animal make a sound ...

### Chemistry

Fluorine reacts with oxygen to yield oxygen difluoride. 2 F2(g) + O2(g)<--> 2 OF2(g) What is the value of K if the following concentrations are found at equilibrium: [O2]= 0.200 mol/L, [F2]=0.0100 mol/L, and [OF2]=0.0633 mol/L Chemistry - DrBob222, Thursday, March 1, ...

### chemistry

A certain monoprotic weak acid with Ka = 6.7 × 10-8 can be used in various industrial processes, but is no longer used in chemistry teaching labs because it tends to explode when it gets old. (a) What is the [H+] for a 0.558 M aqueous solution of this acid and (b) what is its...

### strayer

You and three (3) of your friends were in the same advance placement high school chemistry class in high school. All four (4) of you decided to take the same chemistry class together at the local university along with 21 other students. On the first day of class, the professor...

### Steve look i have corrrected it help plz it urgent anyone plz

Last year kemi who happens to be my sister was 2wice as old as my lovely brillant primary school friend femi,last three years when i was two less than femi age now.the sum of kemi age next 9years and femi age now and my age three year will be equal to 60....what is our present...

### Chemistry

chemistry question. How many grams of silver sulfide can be produced by heating 45 grams of silver excess sulfer?

(I have no idea how to even approach this question. Can anyone please help me?) Some people have proposed that the earth could solve its population problem by shipping people off to space colonies, each containing about 10,000 people. Assuming that we could build such large-...

### chemistry

Carbon and silicon are both in Group 14 of the periodic table. (i) Identify compounds which illustrate similarities in the chemistry of carbon and silicon. (ii)Identify compounds which illustrate significant differences in the chemistry of carbon and silicon. Hence explain why...

### chemistry(oxidation)

ok,I really don't understand the whole oxidation numbers thing my question is state the oxidation number for nitrogen in the following NH3= -3 NO2-1= -1 N2= 0 NO2Cl= 5 N2H4 -2 am I correct? NH3= -3 NO2-1= -1 No, oxygen is -2, so N is +3 N2= 0 NO2Cl= 5 N2H4 -2 http://www....

### CALCULUS-URGENT

we know the series from n=0 to infinity of c(sub n)*3^n converges 1. TRUE OR FALSE the series from n=0 to infinity of c(sub n)*2^n must converge 2. TRUE OR FALSE The series from n=0 to infinity of c(sub n)*4^n must converge 3. TRUE OR FALSE the series from n=0 to infinity of c...

### Plz Check my Geometry (Urgent)

***I know I've posted this several times but it's like getting skipped and or no one has gone over it so I'm posting it one more time before I go to bed. I need to have these checked by tommorrow PLEASE!*** Out of 31 questions these are ones I struggled with. after the = sign ...

part 1 June 30, 2008/2007 Assets Cash- 34,700/23,500 accounts receivable- 101,600/92,300 inventory- 146,300/142,100 Investment-0/50,000 Land-145,000/0 equipment- 215,000/175,500 accumulated depreciation- (53,400)/ (41,300) 2008= 594,000 /2007=442,100 Liabilities and ...

### math

Mrs. Gomes found that 40% of students at her high school take chemistry. She randomly surveys 12 students. What is the probability that at most 4 students have taken chemistry? Round the answer to the nearest thousandth. A)0.008 B)0.438 C)0.562 D)0.665

### chemistry

calculate the volume of 2.27 M Nal that would be needed to precipitate all the of the Hg +2ion from 166mL of a 2.08 M Hg(NO3)2 The equation for the reaction is 2 Nal(aq) + Hg(NO3)2(aq) > HgI2(s) + 2 NaNO3(aq) Please Help I'm really having trouble understanding organic ...

### chemistry

i am doing problems for chemistry class, and some of them are Calculating square root/ Cube Root but some are 4 and 5 instead of 2 or 3. if in a problem the exponent is 4 or 5 how would i use my calculator to calculate the root?

### Chemistry

Analytical Chemistry question: Find the pH and the concentration of each species of lysine in a solution of 0.0010 M lysine*HCL. I know that the pKAs of lysine are (1.77)(CO2H) 9.07 (-NH3) 10.82 ( -NH3) but I am not sure where to go from there.

### Math

Out of 300 student in final year in senior secondary school, 200 are offering biology and the150 offering chemistry how many are offering neither biology nor chemistry

### chemistry

Hello, I was confused on this chemistry problem and I was wondering if someone could please help me. 1) Consider the following chemical reaction: 2CH3OH(I) + 3O2 (g) → 2CO2(g) + 4H2O(I) Calculate the number of moles of CO2 produced when 11.25 mL of methanol CH3OH(I) reacted ...

### ma

In a class of 100 students, 40 failed in Math, 30 failed in Physics, 60 failed in Chemistry. 35 passed in both Math and Physics. 20 passed in Physics and Chemistry. 25 passed in Math and Chemistry. Each student passed in at least one subject. How many students passed in all ...

### chemistry

Would a damp filter paper affect the theoritical yield, calculated actual yield and calculated percent yield. Please help. Chemistry is hard.

### Chemistry

Um how do i balance these word equations for chemistry... I think I'm suppose to look them up on a common table of ions and then I don't know wat to do ferric Oxid --> iron oxygen what exactly am i suppose to do please tel me thr throught process that's suppose to go ...

### chemistry

Effusion/Diffusion Chemistry Help!!! If 4.83mL of an unknown gas effuses through a hole in a plate in the same time it takes 9.23mL of Argon, Ar, to effuse through the same hole under the same conditions, what is the molecular mass of the unknown gas? (146amu) Responses: * ...

### chemistry

I have to answer this question for chemistry. It deals with ionic compounds, like how when an atom loses or gains electrons, energy is involved. So the question is Would the same amount of energy that's taken, be given off? (lost/gained)

### chemistry

i'm having a hard time for my chemistry project an my topic on titration and my topic is to determine the mass percentage of iron in steel wool and i can not get as much information on the steps to follows how to create the titration and equipment needed etc. please can you ...

### Chemistry

Need Help!! Describe how to make 2.5L of 0.1M HCL solution from 12M HCL concentrated solution and water. I got help earlier but still could not figure out the calculations. Please help, it has been a while since i took chemistry. Thank you soo much

### Chemistry

Guys. I have another chemistry question that I am unsure with. I would appreciate it if you could help me with working out. Thanks. A sample of ethane, C2H6, contains 9.6 * 10 ^ 22 atoms. How many mole of ethane is present in the sample? Why do I need to divide (9.6*10^22) by ...

### Chemistry

I have to summarize 10 articles relating to the topics we had covered in class. However, there are 3 sources out of the 10 that I don't understand. Could someone possibly go through the sources and summarize them. 1.) This article covers Nuclear Chemistry (Nuclear Reactors) to...

### accounting ..urgent pls

can you help please.. PROB 1: A, B and C shared the profit of Rs. 9,00,000 in the ratio of 2:2:1 without providing for interest on B’s loan, B granted a loan of Rs. 4,00,000 in the beginning of accounting year. Where as the partnership deed is silent on the interest on loan ...

### chemistry, ap chemistry

At 800 K the equilibrium constant for I2(g) 2 I(g) is Kc = 3.1 10-5. If an equilibrium mixture in a 10.0-L vessel contains 3.56 10-2 g of I(g), how many grams of I2 are in the mixture?

### Chemistry

Balancing chemistry equations and need help! Thank You!? Help balancing any of the following equations: Cl2+Na Br----> NaCl2 + Br Na+LiOH---->

### Chemistry

I need help with Chemistry homework.. I don't know how to write formulas..Please help me! Write the formulas for silicon dioxide.

### accounting ..urgent pls

please help me to solve this problem. THANK YOU AND MAY GOD BLESS YOU ALWAYS. L. Carson agrees to pay \$10,000 each to to C. Ames and D. Barker for 1/3 of their interest in the Ames-Barker partnership. At the time of the admission of Carson, each partner has a \$30,000 capital ...

### Physics Urgent!!!

The 1994 Winter Olympics included the aerials competition in skiing. In this event skiers speed down a ramp that slopes sharply upward at the end. The sharp upward slope launches them into the air, where they perform acrobatic maneuvers. In the women's competition, the end of ...

### Math help urgent

I have a few questions that i need help with so can someone pleese help me thanks:) 1. represent each with an ineqaulity a.) time spent on the activity can be at most 13 mins b.) the volume of the container must be a minimum of 1.8 L and a max of 2.5 L 2. in canada by law any ...

### chemistry

why is chemistry so important

### Chemistry

why is chemistry needed

### Chemistry

Last one I promise! Thankyou for bearing with me. This seems simple enough, but chemistry genuinely makes me feel retarded so I appreciate reassurance. How many molecules of CH4 are there in 48.2g of the compound? I'm assuming that I should just divide 48.2 g by the molar mass...

### Science (urgent)

I have 2 biology questions I really need help with, they are due tommorow and I don't know if I'm right. 1)As an energy carrier, ATP differs from NADPH in that: a)ATP carries less energy than NADPH. b)ATP transfers energy through redox reactions whereas NADPH uses ...

### water treatment

Which is correct for this trickling filter? a)Due to the low BOD loading rate the biomass growth will be too little. Methanol needs to be dosed to keep the biomass alive. b)Due to the high BOD loading rate the filter might clog. This can be prevented by effluent recycling in ...

### Chemistry

A sample of nicotine weighing 0.3204 g was vaporized in a flask with a volume of 487 mL. This sample exrted pressure of 74.3 mm Hg at 20 degrees C. What is the molar mass of nicotine? I know this has to do with N=P*V/R*T. and 1 atm=760 mm Hg. Please help and show work. ...

### Chemistry HELP!!

A sample of nicotine weighing 0.3204 g was vaporized in a flask with a volume of 487 mL. This sample exrted pressure of 74.3 mm Hg at 20 degrees C. What is the molar mass of nicotine? I know this has to do with N=P*V/R*T. and 1 atm=760 mm Hg. Please help and show work. ...

### AP PHYSICS MECH.

Need help urgent!!! A system consist of a ball of M2 and a uniform rod of M1 and length d. The rod is attached to a horizontal frictionless rotates at an angular speed w, as shown in the figure. The rotational inertia of the rod about point P is ? M1 d^2. The rod strikes the ...

### maths

In a class of 80 students, 53 study Art, 60 study Biology, 36 study Art and Biology, 34 study Art and Chemistry, 6 study Biology only and 18 study Biology but not Chemistry. Illustrate the information on a Venn diagram. Determine the number of students who study (I) Arts only...

### CHEM URGENT PLZ

1.Which of these substances has bent molecular geometry around the oxygen atom? Multiple correct answer may apply. a.water b.isopropyl alcohol (rubbing alcohol)** c.acetone** d.diethyl ether. 2.Which of these species are polar? Ignore slightly polar C-H bonds. Multiple correct...

could you please check my work? thanks. For the reaction between reactants A and B below, if 4.925 moles of A is placed into a flask with excess B it is found that the amount of A remaining after 6.85 seconds is 2.737 moles. 2A (g) + B (g)-----> 3 C (g) a. find the rate of ...

### science(chem)

I was just wondering if it was necessary to remember each branch of chemistry learned. I can't really remember general chemistry and I'm sort of loosing the organinc. I mostly remember the calculations and the starting part of each course, but other than that it's hazy. So, am...

### Chemistry

Chemistry help!!!!!!!!!!!? Make a chart and define the following reactions using the following 3 examples methods. Wrie out in letter(a,b,c), Symbol(Na,Cl,O) An name form(sodium,chloride,oxygen) A direct combination b decompition C single replacement and D double replacement