Saturday, April 24, 2010

How many moles of iron, Fe, can be made from Fe2 O3 by the use of 18 moles of carbon monoxide, CO, in the ....

How many moles of iron, Fe, can be made from Fe2 O3 by the use of 18 moles of carbon monoxide, CO, in the following reaction?





Fe2 O3+3 CO--------------- 2 Fe+3 CO2

How many moles of iron, Fe, can be made from Fe2 O3 by the use of 18 moles of carbon monoxide, CO, in the ....
3 moles of CO react with 1 mole of Fe203 to yield 2 moles of Fe





18 moles of C0 react with 6 mols of Fe2O3 to yield 12 moles of Fe





Thierry


How many moles of Hydrogen are needed in order to produce 4 moles of ammonia?

According to the following reaction, how many moles of hydrogen are needed in order to produce 4 moles of ammonia? 3 H2 (g) + N2 (g) ----%26gt; 2 NH3 (g)

How many moles of Hydrogen are needed in order to produce 4 moles of ammonia?
6 moles of Hydrogen


2 moles of Nitrogen


Radioactive Decay - Moles?

Palladium-107 undergoes Beta decay (half-life=6.5E5 yrs.) to form Silver-107. How long will it take for .150 moles of Ag-107 to form from 1.25 moles of Pd-107?





Correct Answer: 1.2E5 yrs





Any idea on how I'd go about doing this? I've tried plugging the moles directly into the formula:





ln(Ao/At)=kt, but I keep getting the wrong answer...





Thanks!

Radioactive Decay - Moles?
You used the natural logarithm.


Then k is 1 /relaxation time.


If you use base 10 you can use k = 1 / half life





Th

night jasmine

How many moles are prepared from????

How many moles of P4S10 can be prepared from 0.25 moles of P4 and 0.25 moles of S8?


There are no other reactants or products.

How many moles are prepared from????
0.2





.25 moles * 8/10


you need 10 atoms of S in the product. The reactant has only 8, so for every .25 moles of S8, you will get .25 * 8/10 of reactant.
Reply:4P4 + 5S8 --%26gt; 4P4S10





You need 5 moles of S8 to react with 4 moles of S4


S8 is the limiting reagent.





0.25 moles S8 x (4/5) = 0.20 moles of P4S10


How many moles of ions are one mole of Ca(OH)2?

the questions starts with: the ions present in Ca(OH)2 are Ca2+ and OH -.





the second part of the questions is how many moles of electrons are in 1 mole of OH minus ions.





Please show me how u did it and what it is that you are doing. THank you very much. Use the above info to answer the question.

How many moles of ions are one mole of Ca(OH)2?
Ca(OH)2 --%26gt; Ca^2+ + 2OH-





From 1 mol of Ca(OH)2, 1 mol of Ca^2+ ions and 2 mol OH- ions are produced, for a total of 3 mol ions.





1 mol OH- has 1 mol electrons, if we're only counting the electron that gives rise to the charge. If we're counting total electrons in OH-, then O has 8, H has 1, and there is 1 electron giving the charge, for a total of 10 electrons in OH-.


Then 1 mol OH- has 10 moles of electrons.


Atoms and moles -Chem- EASY BEST ANSWER!!?

Hello does anyone know the answer to these problems because it'll earn best answer. my answers were wrong.








How many atoms of hydrogen are contained in 100g of methane (CH4)


My Answer: There are 25 atoms of Hydrogen in 100 grams of methane.


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~...


How many moles of P4O10 are produced when we react 8 moles of phosphorous with oxygen?


My Answer: 1.6 Moles

Atoms and moles -Chem- EASY BEST ANSWER!!?
I have checked all of your last questions and saw that all of them are in the same type:


"Mole - Mass - Number of Particles" relationship.





Therefore, rather that to give individual answers, it will be better to teach the concept so that you can solve the questions of the same type.


-----------------------------


Elements have "symbols" and compounds have " formulas". The symbol of an element or the formula of a compound represents their one mole.





For example;


- H2O = 1 mol water, in which 1 mol O and 2 mol H are present.


- NH3 = 1 mol ammonia, in which 1 mol N and 3 mol H are present.





In a chemical equation;


- N2 + 3H2 ------%26gt; 2NH3


1 mol nitrogen (N2) reacts with 3 moles hydrogen (H2) and produces 2 moles of ammonia (NH3).





Now, the number of particles:


1 mole always represents a specific number, called Avogadro's number that is 6.02 x 10^23.





For an element:


1 mole of any element contains Avogadro's number of "atoms" of that element.


1 mol Fe = 6.02 x 10^23 Fe atoms


1 mol Mg = 6.02 x 10^23 Mg atoms.





For a compound:


1 mole of any molecular (covalent) compound contains Avogadro's number of "molecules" of that compound.


1 mol NH3 = 6.02 x 10^23 NH3 molecules.


1 mol H2O = 6.02 x 10^23 H2O molecules.





1 mole of any ionic compound contains Avogadro's number of "formula units" of that compound.


1 mol NaCl = 6.02 x 10^23 NaCl formula units.


1 mol CaO = 6.02 x 10^23 CaO formula units.





Now, we have come to the mass relationship:





The mass of 1 mole of any element is numerically equal to its atomic mass expressed in grams.


For example; atomic mass of Fe is 56. If you have 56 g of iron, this means that you have 1 mole of iron.


Atomic mass of sodium is 23. So, 23 g Na = 1 mole.





If you combine the number of particles, you get 3 relationship:


1 mol Fe = 56 g = 6.02 x 10^23 atoms of Fe


1 mol Na = 23 g = 6.02 x 10^23 atoms of Na


1 mol Mg = 24 g = 6.02 x 10^23 atoms of Mg





The mass of 1 mole of any compound is numerically equal to its formula mass expressed in grams. For example;





H2SO4 formula stands for 1 mol sulfuric acid, in which there are 2 moles of H, 1 mole of S and 4 moles of O. Their atomic masses are 1, 32 and 16 respectively. Therefore, the formula


mass of H2SO4 : (2x1) + 32 + (4x16) = 2 + 32 + 64 = 98





If you have 98 g of H2SO4, this means that you have 1 mole of H2SO4.





Now, lets apply what we have learnt to your questions.





(1) The formula mass of methane (CH4) = 12 + 1x4 = 16


This means that 16 g of CH4 = 1 mole or in other words,


the molar mass of CH4 = 16 g/mol.


16 g CH4 = 1 mol and it contains 4 moles of H atom


then, 100 g CH4 will contain;


4 mol H x (100 g CH4 / 16 g CH4) = 25 mol H atom.


But the question requires "the number of atoms".


1 mole of any element has Avogadro's number of atoms, therefore;


25 mol H x 6.02x10^23 atom/mol = 150.5x10^23


= 1.505x10^25 atom H





(2) Although the question implies a reaction, there is no need to write an equation of the reaction.


The formula of P4O10 states that you will need 4 mol P and 10 mol O to make 1 mol P4O10.


In this question the limiting substance is P (its amount is specified).


Since 4 mol P produces 1 mol P4O10


8 mol P produces (P is doubled, P4O10 is also doubled) 2 mol P4O10. Or,


1 mol P4O10 x (8 mol P / 4 mol P) = 2 mol P4O10.





I think, it is clear and I believe that you can solve your other questions. If not, please inform me. Since you are not one of my contacts, from time to time I look at your profile page to investigate your new questions. Because in answering the questions, the priority is given to those who appreciate my answers.
Reply:25 is the amount of grams of hydrogen, not atoms. Convert 25g of hydrogen to moles, then to atoms using avagrados number. The answer should be 1.49 times 10 to the 24 atoms.
Reply:A lot more hydrogen's than that!





100g CH4 X 1mol/48.42g X 4mol H/1mol C X 6.022 X 10^23





= 4.97 X 10^24 atoms of hydrogen.





Need balanced equation for 2.


How many moles of Aluminum are needed to form 3.4 moles of Aluminum oxide?

Aluminum oxide is formed from the reaction of metallic aluminum with oxygen gas. How many moles of Aluminum are needed to form 3.4 moles of Aluminum oxide? This is a simple ratio problem. Mass is not involved.

How many moles of Aluminum are needed to form 3.4 moles of Aluminum oxide?
The formula for aluminium oxide is Al2O3 (you can just google the term if you want to know the chemical formula for a compound). If you wanted one molecule of Al2O3, you would obviously need two atoms of aluminium. So, if you want 3.4 moles of Al2O3, you would need twice as many moles of aluminium.

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