Moles Definition and 208 Threads

ive been having a hard time with this question and any help would be appreciated. If the percent yield in the reaction of methyl iodide (CH3I) with water to form methanol (CH3OH) and HI is 50%, how many moles of methyl iodide will be required to prepare 0.1 mole of methanol? (Assume that...

Homework Statement I did an experiment and found the weight of CaC(2)O(4)H(2)0 to be 31.4966 subtracted by the weight of a crucible which is 31.2612. I put this for my weight of CaC204H20 (as I can't think of any other weight that it would be requested). I followed the next question...

Hi, I came across this statement and an explanation to this is greatly appreciated as I can't figure this out. "pH 0 means ~ 2 moles of H3O+ for each 100 moles water" ? Thank you.

Homework Statement The are temperature and pressure in a laboratory are 20 degree C and 1 atm. A 1L container is open to the air. The container is then sealed and placed in a bath of boiling water. After reaching thermal equilibrium, the container is opened. How many moles of air escaped...

1. How many moles in 3.00 g H2SO4? Ok first off I don't know to find this answer. I want to know how to find it not just being told the answer. Second I'm going to need to know how to calculate this from beginning to end please help?

Homework Statement Assuming the acid (pain killer) is monoprotic, calculate the moles of pain killer/hydrogen ion in a sample of an unknown pain killer using a titration: NaOH was added to a pain killer solution m[pain killer]=0.40g dissolved in 50 mL of distilled water [NaOH]= 0.15...

I thought this is a pretty easy problem and I can't believe I did it wrong. What did I do wrong? How many moles of ions are present in 250mL of 4.4 M solution of sodium sulfate? Here what I did: 250 mL = .25 L mol Na2(SO)4 = MV = 4.4 * .25 = 1.1 mol but the answer was 3.3 mol

Is calculating the percent yield in moles different than calculating the percent yield in mass? I know that to calculate the percent yield in mass, you divide the actual over the theoretical and multiply by 100. There happens to be a side note in my homework saying that percent yiled can...

The questions is arranged like this: 1.00 mol of oxygen molecules ? oxygen molecules I know an oxygen molecule is 02, so would it be 2 oxygen molecules? It's my first day learning moles, so I'm very lost about the 1.00 mol.

How many moles are in 1kg ice/water?

General question: If given the mass (15.0 g) of a mixture of two solids (NaCl + C12H22O11), can I find the amount of moles in the mixture by multiplying (15.0 g)*(mol / mass NaCl + mass C12H22O11)? I don't think this is valid, but I don't know why not...

Hello. Just need this answer checked. Thanks. If we can reasonably treat acetone vapor as an ideal gas at the Tboil =70° C and we approximate the volume of a Hickman still as ~25mL then how many moles of acetone are in the vapor phase inside the still? (PV=nRT) (R=0.0821 L*atm/mol*K) (Get...

And the solvent for the reaction is going to be 2.5 liters of ether. :bugeye: I hear the t-buLi becomes an instant flame thrower if it is shot out of a syringe. Seriously though, anyone else use this stuff before?

Homework Statement Find the rms speed for an argon atom if 9.0 mol of the gas is confined to a 8.2 liter container at a pressure of 5.4 atm. *I know how to solve the problem, but I forget how to convert 9.0 moles of Argon into moles/kg..how do you do that?? Homework Equations...

Homework Statement *How many moles of LiH are required to make 1 mole of LiAlH4? * 6 moles of LiH will produce how many moles of LiAlH4? Can someone help me get started on these?

[SOLVED] Determine the mass of sodium chloride produced when 2.5 moles of chlorine ga Okay...I know how to solve half the problem. I know how to balance the problem but I'm not sure what to do next. I'm really bad at this stuff. Here's the question: Determine the mass of sodium chloride...

I thought I knew moles inside out, but I havnt quite been told how to factor in what happens when you dissolve something in something. Homework Statement 1.500g of a sample of limestone was dissolved in 50cm^3 of a 1.00 mol/dm^3 of hydrochloric acid solution. The resulting solution was...

[SOLVED] Ideal gas law Please help. I don't know what to do. The air temperature and pressure in a laboratory are 23°C and 1.2 atm. A 1.67 L container is open to the air. The container is then sealed and placed in a bath of boiling water. After reaching thermal equilibrium, the container is...

[SOLVED] Converting Mol 1. A 20-cm-diameter cylinder that is 40 cm long contains 50 g of oxygen gas at 20 degrees celsius. How many moles of oxygen are in the cylinder? so 1 mol = 6.022*10^23 oxygen atomic mass=16g/mol 50g/16(g/mol) = 3.125 mol I don't know why it is wrong...

Suppose Gabor, a scuba diver, is at a depth of 15 m. Assume that: 1. The air pressure in his air tract is the same as the net water pressure at this depth. This prevents water from coming in through his nose. 2. The temperature of the air is constant (body temperature). 3. The air acts...

Calculate the number of moles of O atoms in 13.27 g Mn(NO3)2. Hi I did this question and it seemed pretty easy but there is this online assignment I am doing it for and it says I am not getting the right answer. Please can someone try it and see if they get what i do, or tell me what I am...

I can't understand how both the atomic weight of one atom of an element and the weight in grams of a mole of that element are the exact same thing. For example helium has an atomic mass of 4.0026. That was obtained by adding the amount of protons and neutrons in a helium atom together. On...

Homework Statement A 200g sample of CO2 occupies a volume of 110 L at a pressure of 1 atm. a) What is the number of moles in the gas b) What is the temperature? c) if the volume is increased up to 200 L and the temperature is kept constant. what is the new pressure. Homework...

when you have to work out the amount of moles in 3 grams of magnesiun oxide (2 grams are magnesium) would you go 0.3 divided by 40.31? then the answer is 7.44x10^-3 so that means that's the nuymber of moles of magnesium and also the number of moles of oxygen. So if u had to find the ratio of...

1. :confused: :confused: :confused: i tried some of them but i am not sure if they are right. What is the mass of one mole of aluminum? I don't understand how to do this and What is the mass of one mole of hydrogen? 1.008 g 2.040g 3.000 g 1008 g What is...

chem question please help Homework Statement Ok, so there's .9734 g sample which contained monoprotic benzoic acid C6H5COOH and it's dissolved in 75 mL of water and titrated to the equivalence point with 31.78 mL of .09251 M NaOH solution. a) how many moles of benzoic acid were titrated b)...

Can someone please verify my results? and help me in one-2 questions? I did this lab in school today and had some problems filling in the table that followed. In the lab, we took some Copper Chloride and mixed it dionized water. Then we added in an iron nail and waited for about 20 mins. After...

Homework Statement A chemist studying the rxns of pollutant SO2 places a mixture of SO2 and O2 in a 2.0L container at 900K and an P[init]=1.95 atm. When rxn occurs, gaseous SO3 forms and P falls to 1.65 atm. How many moles of SO3 formed?Homework Equations PV=nRT but I'm not sure what else...The...

How are 0.50 mole sodium carbonate and 0.50 molar sodium carbonate different? Can anyone tell me the diff:?

Homework Statement How many moles is 34.8 of sodium hypochlorite ? Homework Equations 34.8g (1mol/____g) = ______mol The Attempt at a Solution 34.8g (1mol/58.44g) = 2033.712mol Not quite sure if this is how things work, hopefully you can give me a few hints.

Okay, so I was browsing through an AP chemistry book because I really want to major in either chemistry of physics and want to take advantage over thanksgiving break to get ahead on chemistry because I really love it ^^. So I was wondering if someone could check my work on this problem. Thanks...

I am having trouble setting up this problem. Especially part A of the problem. I think I have a good idea of what to do for part B, but could anyone give me any hints on how to find moles from the given information? A 14.0 cm-diameter compressed-air tank is 40.0 cm tall. The pressure at...

Question: 0.2ml glucose solution. Molar mass of glucose = 180 g/mol How many moles? If it was a mass in grams it would be easy: n = mass/molar mass But what do I do now its a volume? Can I still use the same relationship, since grams is equivalent to ml isn't it? If yes, then...

How many moles and numbers of ions of each type are present in the following aqueous solutions? 3.26 L of a solution containing 6.96 x 10^21 formula units of lithium nitrate per liter I got 1.16e-2 mols of Li and NO3 as well as 6.99e21 ions for each. The software I am using (webassign) says...

Hi guys, I know the formula for Potassium Alum is: 2KAl(SO_{4})_{2} * 12H_{2}O Now does this mean that there are 2 Moles of Potassium Alum or 24 moles of Potassium Alum if you include the 12 water molecules? I know when you calculate the molar mass of Potassium Alum, you need to add in...

I need help could someone please help me with this problem? How many atoms are there in 3.90 moles of sulfur (S)?

when determining moles of potassium alum, do you need to count the 12 moles of water also? and how would you do that--just 2 x 12? or something else? soooo confused.

Here is the problem: An oxy-acetylene gas mixture contains 1.05l of acetylene (C2H2) and 2.6L of oxygen both measured at 102 kPa and 298 K. The mixture is contained in a sealed bottle of 5.5L volume. Determine the reacted as shown here ( 2C2H2(g) +5O2(g)  4CO2(g) + 2H2O(g) ) and the...

Hi, can some one pleas tell me how to do these questions? Thanks. How many atoms of C are in a mixture containing 0.237 mol of CO2 and 2.38 mol of CaC2? calclate the following the mass (g) of one atom of xenon the mass (g) of one mole of xenon atoms the number of atomic mass units in...

How do I figure out how many moles to mutiply by? It says "multiply by the number of moles of that substance" How do I figure that out? Here's where I am: H2O(l)= - 285.830 kJ/mol x ___ mol NH3(g)= -46.11 kj/mol x ___ mol --- And what does the L or G mean for the equation?

would someone be kind enough to explain througly the concept of moles...i have missed classes on that part of the unit and need to get a better grasp of it...the text is not helping...if anyone can do it in a step by step type of way...i would greatly appreciate it...thank you ahead of time.:smile:

I was given several equations to use for this assignment so, before assuming that I got this right, I wanted to check my answers. I don't think I have them done correctly...:redface: What is the molarity of a solution of silver perchlorate, AgClO4, if 3.2 moles of silver perchlorate are...

here's a question from my recent chem exam that i don't know how to approach: a sample of 0.600 mol of a metal M reacts completely with excess fluorine to form 46.8 g MF2 a) how many moles of F are in the sample of the compound that forms? b) how many grams of M are in this sample of...

BY only given the mass of air in a certain sample, how would one calculate the number of moles of air in the sample? n = m / mass per mole however, what's mass per mole? and how would you solve for it? thanks.

Q: A chemist is studying one of the five oxides of nitrogen: N2O, NO, N2O3, NO2, or N2O5. He learns that 250mL of the gas has a mass of 0.335g. Which oxide is he working with? To get an answer, I would first calculate the mL of each substance, but how? I only know that one mol=22.4mL at STP...

Suppose you want to heat the air in your house with natural gas (CH_4). Assume your house has 275 m^2 of floor are and ceilings are 2.5 m from floors. The air in your house has a specific heat capacity of 29.1 J/mol K. The number of moles in the house can be found by assuming the molar mass of...

How many moles of ions are present in aqueous solutions prepared by dissolving 10.00 g of the following compounds in water to make 4.35 L of solution? (a) cobalt(III) chloride (b) aluminum carbonate (c) potassium permanganate (d) strontium hydroxide I first converted the 10.00 g into...

hi folks.. I am having some problem here, and i dun know how to solve it.. some mole calculation. i would like ask help from u guys.. many thanks.. questions are below: [can give me the working process in details?] 6. A report states that biogas is 60% methane (relative molecular mass =...

hi guys, need help with a question. i know how to get the amount of a substance in moles from something like NaCl in 5.85g of salt you just use n = m/M but would like to know how to: calculate the amount(in mole) of: cl ions in 13.4 g of nickel chloride(NiCl2) i know the answer i...

How would you go about changing liters, like 1L into moles? Thanks