Stoichiometry

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Combustion reaction of C4H10O

Consider the following reaction: C4H10O + 6O2-> 4CO2+5H2O deltaH=-2713kj How many grams of water will be produced if the reaction is conducted with 75.6g of C4H10O and 95.5 g of oxygen?

A sample of unknown Y is subjected to elemental analysis

1. A sample of unknown Y is subjected to elemental analysis. The follwoing precentages by weight are found to be: C 40.0% H 6.7% O remainder of % by weight The molar mass is found to be 60.0 g A. Calculate the empirical formula (show work) B. What is the molecular formula of unknown Y. (Inclu

Combustion Reaction Problem

Consider the combustion of methane, CH4 CH4 (g) + 202 (g) ----> CO2 (g) + H2O (g) Suppose 8.00g of CH4 is allowed to burn in the presence of 6.00g of 02. How much (in grams) CH4, 02, CO2, and H2O remain after the reaction is complete? Please show the required calculations.

Calculate amount of moles from dissolution

How many total moles of ions are released when each of the following samples dissolves completely in water? (a) 0.24 mol of Na3PO4 mol (b) 51.4 g of NiBr2 3 H2O mol (c) 4.07 1022 formula units of FeCl3 mol

Molecular Weight Molarity

Please assist with creating 1.0 M solution with 5.21 grams of Na2CO3. I need to create 1.0 M solution with 4.12 grams of NaHCO3 . How much distilled water to is use to create these 1.0 M solutions.

Formation of a gas

A solution containing an unknown amount of methyl alcohol that is dissolved in n-octane is added to an excess of methylmagnesium iodide which is dissolved in the high boiling solvent, n-butyl ether. A gas is evolved from the reaction. The gas is collected and its volume determined to be 1.04 ml (corrected to STP). What is the

Molarity Problem Explanation

1. Calculate each of the following quantities. a. grams of solute in 173.4 mL of 0.207 M calcium acetate b. molarity of 576 mL solution containing 21.1 g of potassium iodide c. moles of solute in 145.6 L of 0.726 M sodium cyanide 2. Assuming that the volumes are additive, what is the concentration of KBr in a solution prep

Average Density of the Sun

I need some help figuring this question out: The sun has estimated mass of 2x10^36 and the sphere is of average radius of 6.96x10^5 km, calculate the average density of the sun in units of kg/km^3; kg/m^3; g/cm^3 and lbs./ml (hint: use answer from c to convert).

How many liters of CO2 gas are released?

When 10 grams of calcium carbonate are treated with 50 ml of HCl which has a density of 1.096g/ml the calcium carbonate dissolves giving a solution and releasing CO2 gas. The solution weighs 60.4g. How many liters of CO2 gas are released? The density of the gas is 1.798grams/liter

Natural Phenomena Experiment

My son needs to demonstrate an experiment that can explain natural phenomena or the world of everyday experiences using scientific methods and employ theories to interpret his observations. Any ideas, material lists and steps would be helpful.

Modifying the determination of density of a solid in water

How would you modify the determination of density of a solid if the solid dissolved in water, as sugar does? Would your density measurements be more precise if you used a balance that weighed to more decimal places, but still used the same graduated cylinder for determining the volume?

Mole problem - package of M&M candies contains 50 pieces

A package of M&M candies contains 50 pieces. What fraction of a mole is this? Express in both normal and scientific notation. A package of 50 m&m candies cost 50 cents. How much would a mole of m&m's cost in dollars? Given the annual budget of the US is 2 trillion dollars, how many years would it take the US to pay for a mol

Mole problem - The volume of an M&M candy

The volume of an m&m candy is .65 mL. What volume in cubic meters, would one mole of m&m candies occupy? Next, compare the volume of a mole of m&m's to lake erie, which has a volume of 116 mi^3. How many lakes the size of lake erie would a mole of M&M candies fill.

Find number of protons, electrons, neutrons

Given the atomic number and the mass number of an atom how do we determine the number of protons in the nucleus? The number of neutrons in the nucleus? The number of electrons in the surrounding shells?

Atomic number and mass number

Solutions, Density, Molecular weight

The alcohol content of hard liquor is normally given in terms of the "proof", which is defined as twice the percentage by volume of ethanol (C2H5OH) present. Calculate the number of grams of alcohol present in 1.00 L of 51 proof gin. The density of ethanol is 0.798 g/mol. (solution in grams) Arginine vasopressin is a pitui

Solutions, Density, Molecular weight

Determining a molecular formula

Thriophene is a carbon-hydrogen-sulfur compound used in the manufacture of pharmaceuticals. When burned completely in excess oxygen, its combustion products are CO2, H2O, and SO2. Combustion of a 0.535 g sample yields 1.119 g CO2, 0.229 g H2O, and 0.407 g SO2. What is the empirical formula of thiophene? The molar mass of thiophe

the percent abundance of each isotope of chlorine

Chlorine has two naturally occuring isotopes, 35 Cl (isotopic mass 34.9689 amu) and 37Cl (isotopic mass 36.9659 amu). If chlorine has an atomic mass of 35.4527 amu, what is the percent abundance of each isotope?

Molar Volume from solution samples

I have premass samples of NaCl (1.16 grams) and CaCl2 (2.24 grams), I need to create a 1.0M solution of both slats using distilled water. How much distilled water do I use per salt?

Stoichiometric Conversions

An empty vial weighs 55.32g. 1) If the vial weighs 185.56g when filled with liquid mercury (d=13.53 g/cm^3), what is its volume? 2) How much would the vial weigh if it were filled with water (d = 0.997g/cm^3 at 25 degrees Celsius)? [show all your steps in answering this question] Volume of the vial.

Structures of Hydrocarbons

Unlike cyclopentadiene, 1,3 cyclohexadiene can be stored for long periods at room temperature. When 1,3 cyclohexadiene is heated at 180 degrees C for two hours, a 30% yield of two products A and B, each of empirical formula C12H6, can be isolated. Hydrogenation of either A or B gives the same hydrocarbon C, of empirical formula

Finding atoms in a sample

Avogradro's number (6.022 x 10^23 atoms/mol) is a useful number that can be used to calculate a number of different values for compounds/elements. One important value is finding the number of atoms in a specific mass of an element. The solution includes a general step-by-step method of finding the number of atoms in a specific

Molar problem of Iron(III)nitrate

Question: If you want to make 2.5 liters of a 1.2 Molar solution of Iron(III)nitrate, how many grams of Iron(III) nitrate would you need to weigh out? This is a beginners easy class, so the teacher keeps it simple and not complex. We figure out the problems using conversion factors and I want to know how to set it up and h

Aluminum Nitrate

How many grams of aluminum nitrate would be needed to make 0.95 ml of a solution with a normality of 3.2? I need to know how to set up this problem and then make sure I end up getting the right answer on the calculator.

Molal Solution/Mass of Water and Mole Fraction

What mass of water must be used to dissolve 20.0 g of C2H5OH to prepare a 0.0500 molal solution of ethanol? 8.70Kg how? Calculate the mole fraction of ethyl alcohol C2H5OH in a solution that contains 230 grams of C2H5OH and 312 grams of benzene C6H6? 0.56 How?

Molality/Molarity Calculations

Please help me calculate the molality of a solution that contains 51.2 g of C10H8 in 500 ml of carbon tetrachloride. The density of CCl4 is 1.60 g/ml. I also need help calculating the molarity of a solution that contains 9.0 g of (COOH)2 in 1500 ml of solution.

Molarity and Mass

A 30.0ml sample of a solution of NaCLO3 that contains 1.06 g of NaClO3 is to react with a solution of I2. What is the molarity of the NaClO3 solution? Also, what mass of Molybdenum3 oxide, Mo2O3 will be completely oxided to potassium molybdenum, K2MoO4 by 35.Oml of .200 MkMnO4.

Reaction of FeSO4 and KMnO4

An impure 0.500 gram sample of FeSO4 reacts with 20.0 ml of 0.0200 M KMnO4 Assuming that the impurities do not react with KMnO4 what is the percentage of FeSO4? The equation given is MnO4- +8H +5Fe+2 -------->Mn2 +5F3+ + 4H2O so far I got: .0200l *.0200M MnO4- =4*10-4 Moles of MnO4 How do I get to the moles of Fe?

the mass of CuO in the mixture

A 0.500 gram mixture of Cu2O and CuO contains 0.425 grams of Cu. What is the mass of CuO in the mixture? I have the answer it is .21 grams of CuO I just need a formula and step by step instructions on how to arrive at this answer. I would love this answer back as soon as possible thank you. -Paul L. Hollis