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Stoichiometry

Stoichiometry and Heating Zinc Sulfide

Heating zinc sulfide in the presence of oxygen yields the following: ZnS + O2 (arrow) ZnO + SO2 If 1.72 mol of ZnS is heated in the presence of 3.04 mol of O2, which reactant will be used up? Balance the equation first.

Concentration of Stock Solution

Please explain how I would figure out this problem: From 0.80 L of a glucose stock solution, 4.0L of a 1.8% w/v solution of glucose was prepared. What was the concentration of the stock solution?

Reaction of KCl and HNO3

How many grams of KNO3 can be made from 591.9 g KCl and 830.0 ml of 12.0 M HNO3 by the reaction: KCl (s) + HNO3 (aq) ----> KNO3 (s) + Cl2 (g) + NOCl (g) +H2O (I) Also, how much of the excess reactant (grams if KCl or ml if HNO3) will be unused?

The fluoride ion is very toxic.

The fluoride ion is very toxic. Not only does it interfere with glycolysis, but if forms an insoluble precipitate with calcium ions (Ksp = 4.13 x 10-11). Give an explanation as to why CaF2 is insoluble; whereas, other calcium halides are soluble in the order CaI2>CaBr2>CaCl2. How much fluoride (as sodium fluoride) would you h

Stochiometery 4

When 19.8g butane, C4H10 is burned with excess oxygen: 2C4H10g + 13O2g -----> 8CO2g +10H2Og How many grams of oxyen are consumed, how many grams of CO2 & H2O are produced?

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

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?

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

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, please) Arginine vasopressin is