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Stoichiometry

Example of Lab Report: Decomposition of Potassium Chlorate

Calculate and record the following for the experiment performed with 10.000 g KClO3 1. (a) mass of the crucible with manganese(IV) dioxide (in grams) = 53.300g (b) mass of the crucible after potassium chlorate has been added (in grams) = 63.300g (c) mass of the crucible after heating (in grams) = 59.383g (d) mass of po

Finding the Age of a Rock Using Radioactive Decay Data

(1) The half life of U-238 is 4.51x10^9 yrs. In a rock containing N atoms of U-238, how many Helium atoms are produced by radioactive decay of U-238 to Pb-206 in 4.51x10^9 yrs? (2) A rock is analyzed for its helium and uranium content and found to contain 1.00x10^-9 mole of U-238 atoms, and 2.00x10^-9 mole of Helium atoms. As

Concentration of Lead in Soil from Mine Tailings

Lead from mine tailings containing 0.6 % lead was applied at a rate of 12 metric tons per acre of soil and worked in to a depth of 20 cm. The density of the soil is 1.8 g/cm3. To what extent does this add to the burden of lead in the soil? (There are 640 acres per square mile and 1609 meters in a mile.) a) 19 ppb b) 45 ppb

Calculations required for a typical "Calculation of Gas Constant" lab report.

Example of Gas Law Constant Lab Report PLEASE SEE THE ATTACHED FILE FOR THE FULLY FORMATTED PROBLEM 1. A student performs the experiment according to the instructions in this experiment. (SHOW WORK in spaces provided) a. The weight of magnesium ribbon used is 0.0328 grams. How many moles of hydrogen could be collected

Chemical Reaction

What volume of 0.5 M H2SO4 is needed to react completely with 20.0 ml of 0.4 M LiOH?

Titre Calculations and Reactions

1. 20.0ml of calcium lactate solution was diluted with 30ml of water, to give a titre value of approximately 20ml of 0.05M disodium edetate. What would you expect the approximate titre value to be if the calcium lactate had been dissolved in 60ml of water? 2. How many moles of disodium edetate react with each mole of calcium

Synthesis of a chemical compound: Making alum from aluminum

How do I calculate the amount of alum left over in the following problem? Experiments show that solubility of alum in 25 mL of 1.4 M KOH plus 10 mL of 9M H2SO2 is about 1.0 g at 1.0 oC and 1.7 g at 6.0 oC. Using your measured solution temperature (4.5 oC) estimate the amount of alum left in your chilled solution

mass percent and volume percent of ethyl alcohol in solution

Ethyl alcohol, C2H6O is the alcohol present in liquor. A solution is made up by adding 25.0 mL of ethyl alcohol (d = 0.789 g/mL) to 45.0 mL of isopropyl alcohol, C3H8O (d = 0.7855 g/mL). Assuming volumes are additive, calculate the following: The mass percent of ethyl alcohol in the solution. Ethyl alcohol, C2H6O is

Energy Required to Produce

9. Find the energy required produce 1kg of Al from native Al2O3 and compare this with the energy required to melt 1kg of aluminum in a recycling plant.

If 42.50 ml of solution of 100grams

If 42.50 ml of solution of 100grams of potassium chromate per liter was used to completely react with a sample of 10 grams of soluble lead (II) salt, what is the percentage of lead (II) in the sample

Making a Buffer

How would I make a 10% NaCl 100ml buffer made up from a 5M NaCl stock solution. The NaCl stock is aqueous solution.

Calories from Fat

A person on a 2500-Cal low-fat diet attempts to maintain an intake of no more than 20% of food energy from fat. What percent of the daily fat allowance is represented by a tablespoon of peanut butter (15.0 g and 50.1% fat)? Fat has a food value of about 9.0 Cal/g. A. 14 % B. 27 % C. 2.7 % D. 0.17% E. 5.4 %

Iron Production in a Reaction

How many grams of iron can be produced from 3.50 Kg FeO3 from the following reaction FeO3(s) + 3CO (g)-------->2Fe (s) = 3CO2 (g)

Anaerobic Respiration with Ethanol

If the Density of Ethanol is 0.789 g/ml, Starting with 1.00 Kg of glucose, what is the maximum amount of ethanol in grams and liters that can be obtained by the process of the following reaction C6H12O6 (I)__----> 2 C2H5OH (I) + 2 CO2 (g)

Consumption

From the following reaction please calculate the grams of sulfur dioxide, SO2 produced when a mixture of 50.0 g of carbon disulfide and 72.0 grams of oxegen reacts. Which reactant remains unconsumed at the end of the combustion. How many grams remain? CS2 + 3O2 ----> CO2 + 2SO2

Benzene and bromine react from bromobenzene

Benzene and bromine react from bromobenzene, as represented by the equation. The densities of benzene and bromobenzene are 0.879 g/ml, respectively. How many mL of bromobenzene can ce prepared from 12.5 mL benzene? C6H6 + Br2 --> C6H5Br + HBr

Mole, Empirical and Stoichiometry Calculations

Mole Calculations (Determining Avogadro's Number): 1. Calculate the mass of carbon in a diamond that contains 3.33 x 1024 atoms of C. 2. Calculate the mass of chloroform that contains 1,000,000,000,000 molecules of CHCL3. 3. Calculate the number of NaCL formula units in 1.37 g of table salt. 4. Calculate the number of N2 mo

The Production of Sulfur Trioxide

SO3 can be produced in the following two-step process: FeS2 + O2 ---> Fe2O3 + SO2 S02 + O2 ----> SO3 Assuming that all the FeS2 reacts, how many grams of SO3 are produced when 20.0 g of the FeS2 reacts with 16.0 g of O2?

Stoichiometric Relations Chemistry

The equation for one of the reactions in the process of reducing iron ore to the metal is Fe203(s) + 3CO(g) ??> 2 Fe(s) + 3 CO2(g) a. What is the maximum mass of iron, in grams, that can be obtained from 454 g (1.00 lb) of iron(III) oxide? b. What mass of CO is required to reduce the iron(III) oxide to iron metal?

Chemistry

A car gets 9.2 kilometers to a liter of gasoline. Assuming that gasoline is 100% octane (C8H18), which has a density of 0.69 g/cm3, how many liters of air (21% oxygen by volume at STP) will be required to burn the gasoline for a 1250-km trip? Assume complete combustion.

Ultraviolet Radiation in Fluorescence

In the process called fluorescence some substances absorb photons of one kind of radiation (ultraviolet) and give out photons of a different kind, when infrared radiation falls on these materials, visible light is not emitted, why? no further info re fluorescence needed, and which element results if two protons and two neutrons

Balanced chemical equation for biosynthesis

Please help with the following problem. Write the balanced chemical equation for the biosynthesis of ethanol. Label the sucrose and the ethanol in the equation. If you start with one mol sucrose, how many mol ethanol is produced? (Assume complete conversion of sucrose to ethanol.) The density of ethanol is 0.80 g/ml. A

Moles of Sulfur Dioxide

How many moles of Sulfur dioxide are in 1.07 x 10 ^23 molecules of sulfur dioxide? And how many molecules are in 58.1 g of Butane?

Moles in Bromine

How many moles are in 8.50 mL of liquid bromine if the density of bromine is 3.12 g/mL?