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1.946 moles NaCl (58.44 grams/1 mole NaCl)
= 113.7 grams sodium chloride
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Calculate the molarity of a solution of ethanol in water in which the mole fraction is 0.040 assume that the density of water to be one?
It depends a bit on what information you are given. However, the principle is the same in all cases, although how you do the specific calculation may vary a bit.As an example, let's say we have a mixture of 5.00 grams of water and 10.0 grams of ethanol (C2H5OH). What is the mole fraction of the two components?The first thing we must do is convert the number of grams of each substance into moles. To do that, see the Related Question below:How do you convert from grams to moles and also from moles to grams?For water, we have:5.00 grams ÷ 18.015 grams/mole = 0.2775 moles H2OFor ethanol, we have:10.0 grams ÷ 46.068 grams/mole = 0.2171 moles C2H5OHNow we can find the mole ratio, which is defined as follows:Moles ratio of compound X = number of moles of X ÷ total number of moles in mixtureSo the mole ratio of water is: 0.2775 ÷ (0.2775 + 0.2171) = 0.561 or 56.1%and the mole ratio of ethanol is: 0.2171 ÷ ((0.2775 + 0.2171) = 0.439 or 43.9%Check your answer! The total mole ratio for all components MUST add up to 1.00:0.561 + 0.439 = 1.00 Yes!Note that the weight ratio was 1-to-2 (twice as much ethanol as water by weight), but the mole ratio was completely different.
How many moles of Fe are present in 30 grams in rust?
This amount may be different because rust is not a clearly definite compound.
How many moles are in 272g?
It depends on what the subtance is, i.e. whether there is 272g of copper, sodium chloride, lithium hydroxide or what. The way to calculate the amount of a subtance in moles is to divide the mass of the substance (in grams) by the atomic mass, molecular mass or formula mass of the element, molecular compound or ionic compound respectively, as the case may be.
What are dermal moles?
Dermal moles, which range from flesh-color to brown, are elevated, most common on the upper body, and may contain hairs.
How many moles of calcium are in 15.5 g calcium chloride?
If grams/molar mass=moles, then first the molar mass of the compound must be found. CaCl2 has a molar mass of 110.984. Divide the number of grams, 15.5, by 110.984, and you get the number of moles. Now, seeing as calcium is not diatomic like oxygen or chlorine, there needs to be no conversion between the number of moles of calcium in the compound and the number of moles of calcium outside of the compound. atoms, the number of calcium atoms in the compound divided by one mole of the compound will give us the ratio. Conveniently enough, that ratio is one calcium atom per molecule of calcium chloride, meaning that for every one mole of calcium chloride, 1 mole of pure calcium can be extracted. So once you find the number of mole of CaCl2, that is the number of moles of calcium as well. This may be a little difficult to grasp, but I'm sure that your teacher, if you're a student, will be able to explain why rather well.
How may grams of KNO3 should be used to prepare a 2.0L of a 0.50 M solution?
Get moles by; Molarity = moles of solute/Liters of solution 0.50 M KNO3 = moles KNO3/2.0 L = 1.0 mole KNO3 Now find grams of 1.0 mole KNO3 1.0 mole KNO3 (101.11 grams/1 mole KNO3) = 101.11 grams KNO3 needed call it 100 grams
How do you solve limiting reagent problems?
AnswerUnderstanding limiting reagent problems, and being able to solve them, is essential for determining how much of each reactant is needed when performing a reaction, and will also tell you how much of each product will be formed in the reaction. The amount of products formed is determined by the limiting reagent.Before solving a limiting reagent problem, you MUST first do a couple of things: you must write the balanced chemical reaction and you must determine the stoichiometry of the reaction. Instructions on how to do both of these things can be found under the Related Questions links to the left.Once you have written the balanced the reaction, and determined the stoichiometry, you must compare two (or more) calculations to determine which reagent is the limiting reagent and which one is in excess.The limiting reagent is the chemical which will effectively determine the amount of products that are formed. In other words, the limiting reagent is the chemical which will run out first as the reaction occurs and the reactants are consumed. The other reactants, the ones are are leftover when the limiting reagent runs out, are said to be in excess.Which chemical is limiting and which is in excess is ALWAYS a function of the stoichiometry and the number of moles, and NEVER the number of grams of the reagents. You must always compare the numbers of moles with the stoichiometry of the reaction.Let me explain how to solve the problem with an example.Suppose 2.00g of NaCl reacts with 5.00g of AgNO3 to form NaNO3 and AgCl. First we must write the balanced equation, which is:NaCl + AgNO3 ---> NaNO3 + AgClNow we must determine the stoichiometry, which is this case is very simple. The ratio of all species in the reaction is one-to-one. In other words, for one mole of NaCl, one mole of AgNO3 reacts with it, and one mole of NaNO3 and one mole of AgCl are formed.Now we must determine which reagent is limiting: the NaCl or the AgNO3. As I said, everything must be in terms of moles, and so we must convert the number of grams of each into moles:2.00 grams of NaCl ÷ 58.4425 grams/mole = 0.03422 moles NaCl5.00 grams of AgNO3 ÷ 169.987 grams/mole = 0.02944 moles AgNO3The stoichiometry of the reaction says that the number of moles of NaCl and AgNO3 should be equal, but as you can see, in this case they are not the same. There are more moles of NaCl than AgNO3. That means that AgNO3 is the limiting reagent, and NaCl is in excess because there is more NaCl than can react with AgNO3. That means that 0.02944 moles of NaCl will react with 0.02994 moles of AgNO3, and 0.02944 moles of NaNO3 and 0.02944 moles of AgCl will be formed.From this we can say how much NaCl will be left one: the amount that we started with minus the amount that reacted:0.03422 - 0.02944 = 0.00478 moles of NaCl in excess.Note that NaCl is in excess even though there were fewer grams of NaCl than there were of AgNO3! It's about MOLES and notgrams.Let us do another example with more complicated stoichiometry.Suppose 20.0 grams of magnesium hydroxide, Mg(OH)2, reacts with 40.0 grams of phosphoric acid, H3PO4 to form magnesium phosphate, Mg3(PO4)2, and water, H2O. The balanced reaction is:3Mg(OH)2 + 2H3PO4 --> Mg3(PO4)2 + 6H2OAs you can see the stoichiometry here is more complicated, and the ratios are 3 to 2 to 1 to 6. Again, the next step is to convert grams to moles.20.0 grams Mg(OH)2 ÷ 58.324 grams/mole = 0.3429 moles Mg(OH)240.0 grams H3PO4 ÷ 97.990 grams/mole = 0.4082 moles H3PO4As you can see, there is more H3PO4 than Mg(OH)2, so it may seem that it is in excess but always reason out your answer and check it using stoichiometry. The stoichiometry of the problem says that for every 3 moles of Mg(OH)2, there needs to be 2 moles of H3PO4. Therefore the limiting reagent is Mg(OH)2 because there clearly isn't 3/2 (1.5 times) the number of moles of H3PO4 provided. Mg(OH)2 is the limiting reagent and H3PO4 is in excess. To check this (if you can't do the math in your head), you can do the calculation using the 2-to-3 stoichiometry of the reaction:0.3429 moles Mg(OH)2 * 2 mol H3PO4/3 mol Mg(OH)2 = 0.23 moles H3PO4 requiredand clearly 0.4082 is more than 0.23.You can also check it this way: there should be 3/2 (1.5 times) as much Mg(OH)2 as H3PO4:0.4082 moles H3PO4 * 3 mol Mg(OH)2/2 mol H3PO4 = 0.32 moles Mg(OH)2 requiredand since 0.3429 (moles provided) is less than 0.32 (moles needed) Mg(OH)2 is the limiting reagent and H3PO4 is in excess.Because Mg(OH)2 is the limiting reagent, the amount of products formed is determined by the number of moles of the limiting reagent in this case the Mg(OH)2. For each mole of Mg(OH)2, 1/3 moles of Mg3(PO4)2 is formed (because of the 3-to-1 ratio), and 2 moles of H2O are formed (because of the 3-to-6 ratio). So to find the number of moles of products, multiply the number of moles of Mg(OH)2 by 1/3 and 2 respectively:0.3429 moles Mg(OH)2 * 1/3 = 0.1143 moles Mg3(PO4)2 formed0.3429 moles Mg(OH)2 * 2 = .6858 moles H2O formedStudent 09 12:41, 20 Aug 2009 (UTC)sorryI think the answer wasnt right.Suppose to be every 3 moles of Mg(OH)2, there needs to be 2 moles of H3PO4.finally the answer is Mg(OH)2 will be the limiting reagent.This is my own opinion and i think this is the correct one. i jope that someone can please check on this. if me wrong,do correct me please,,thank younot sure what the person who wrote out all the problems did for the second example, but after you find the moles of both reactants, you're supposed to divide the number of moles by the coefficient. my calculations were a bit off from the other person's, but this is pretty much what i got:20.0g Magnesium hydroxide= 0.34 moles * 3 (the coefficient) = 1.0240.0g phosphoric acid= 0.41 moles * 2 (the coefficient) = 0.821.02>0.82, therefore, the phosphoric acid must be limiting.
Calculate the molarity of a solution of ethanol in water in which the mole fraction is 0.040 assume that the density of water to be one?
It depends a bit on what information you are given. However, the principle is the same in all cases, although how you do the specific calculation may vary a bit.As an example, let's say we have a mixture of 5.00 grams of water and 10.0 grams of ethanol (C2H5OH). What is the mole fraction of the two components?The first thing we must do is convert the number of grams of each substance into moles. To do that, see the Related Question below:How do you convert from grams to moles and also from moles to grams?For water, we have:5.00 grams ÷ 18.015 grams/mole = 0.2775 moles H2OFor ethanol, we have:10.0 grams ÷ 46.068 grams/mole = 0.2171 moles C2H5OHNow we can find the mole ratio, which is defined as follows:Moles ratio of compound X = number of moles of X ÷ total number of moles in mixtureSo the mole ratio of water is: 0.2775 ÷ (0.2775 + 0.2171) = 0.561 or 56.1%and the mole ratio of ethanol is: 0.2171 ÷ ((0.2775 + 0.2171) = 0.439 or 43.9%Check your answer! The total mole ratio for all components MUST add up to 1.00:0.561 + 0.439 = 1.00 Yes!Note that the weight ratio was 1-to-2 (twice as much ethanol as water by weight), but the mole ratio was completely different.
How many moles of carbon atoms are there in 3 grams of carbon?
The questions asks how many moles of carbon atoms.Molar mass is defined as the mass of one mole of a substance or in this case 6.022x1023 atoms of carbon. So the molar mass for carbon is 12.0 g/mol. Therefore the number of moles of carbon atoms is just 36/12.0 = 3.0 moles of carbon.How many atoms are in 36 grams of Carbon?[36 (gC) /12.0 (gC/molC)] * 6.02*10+23 (atoms C/molC) = 1.8*10+24 atoms in 36 g Carbon
How many moles of Fe are present in 30 grams in rust?
This amount may be different because rust is not a clearly definite compound.
What is equivalent weight of Sodium Hypochlorite. Also explain why?
Sodium hypochlorite NaOCl may react with two moles of HCl, NaOCl + 2HCl = NaCl + Cl2+ H2O, so its molecular mass divided by 2 is its equivalent mass.
Given a stock solution of 0.5 M NaCl describe how you would prepare 100ml of 2M of the solution of NaCl?
You need to know the gram molecular mass (in this instance, since sodium chloride is an ionically bonded compound and does not have moles in the strictest sense, more properly the gram formula unit mass) of sodium chloride, which is 58.44. The number of grams required may be calculated as set forth below. By definition, a 0.05M solution contains 0.05 moles of solute (sodium chloride in this instance) per liter of solution, and there are 1000 ml per liter. Therefore, the number of moles required for the specified amount of 0.05M solution is 0.05(125/1000) or 0.00625. The amount of sodium chloride required is therefore 0.00625(58.44) or 0.4 grams, to the justified number of significant digits, which is limited by the fact that the molar concentration stated has only one significant digit. If 0.05 were interpreted as having at least three significant digits, then the answer would be 0.3652 grams.
When was Manuel Moles born?
Manuel Moles was born on May 2, 1940.
What day of the week May 7 1946?
May 7, 1946 was a Tuesday.
What day of the week was May 16 1946?
May 16 1946 was a Thursday.
What day of the week was 25 may 1946?
25 May 1946 was a Saturday.
What day of the week was May 3 1946?
3 May 1946 was a Friday.
