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Stoichiometry

Air bags

Air bags are activated when a severe impact causes a steel ball to compress a spring & electrically ignite a detonator cap. This causes sodium azide(NaN3) to decompose explosively: 2NaN3(s) = 2Na(s) + 3N2(g) What mass of NaN3(s) must be reacted to inflate an airbag to 70.0 L. at STP?

Show work-Oswald process - mass and how much oxygen required?

9) Industrially, nitric acid (HNO3) is produced by the Oswald process represented by the following - what mass of NH3 is needed to produce 5 tones of HNO3? How much Oxygen is required? 4NH3 + 5O2 = 4NO = 6H20 2NO + O2 = 2NO2 2NO2 + H2O = HNO3 + HNO2

Chemical equation with 7 parts

(Any number following an asterisk is a subscript.) Using the balanced chemical equation: C*6H*12O*6 + 2H(positive charge)--> C*6H*14O*6 answer the following A. How many grams of C*6H*12O*6 equals one mole? B. How many grams of C*6H*14O*6 equals one mole? C. How many moles of H(positive charge) react with 1 mol of C*6H*12O*

A equation with 9 parts

(any number following an asterisk is a subscript) Using the equation for the combustion of methane: CH*4(L) + O*2(G) --> CO*2(G) + H*2O(G) answer the following: A. Is the equation properly balanced and if not balance it. B. Name the compounds in this reaction. c. How many moles of O*2 react with 1 mol of CH*4? D. How many

Solubility product constant

A saturated solution of silver chloride, AgCl contains 1.92 mg of AgCl per liter of solution. What is the value of the solubility product constant Ksp for silver chloride? I know that soluability for AgCl at 25 degrees celcius ksp = 1.8 x 10 -10, however I am not sure if I would even need to incorporate this into the equatio

This deals with limiting reactants in stoichiometry

If 350.0 mL of 6.00 M H2SO4 reacts with 45.00 grams of Al in the following reaction, what is the limiting reagent, how many moles of excess reagent will there be, and how many liters of H2 will form? The reaction is: H2SO4 + Al produces Al2(SO4)3 + H2 If you could please show the steps, I'd appreciate it.

Stoichiometry problem dealing with limiting reagents

If 275.0 mL of 0.5000 M ZnCl2 reacts with 1.650 x 10 to 23rd power of AlPO4 compounds in the following reaction, what is the limiting reagent, how many moles of excess reagent will there be, and how many grams of each product will form? 3 ZnCl2 + 2 AlPO4 yields Zn3(PO4)2 + 2 AlCl3 I am substitute teaching, and I would lik

Calculating Molarity and Molality

Question: A sodium chloride solution has a molarity of 1.250 mol/L and a density of 1.050 g/ml. Calculate molality, the mole fraction of water, and the percent by mass of sodium chloride.

Solve: Distance, Velocity, Density and Volume

Questions: 1. If the sun which is 93,000,000 miles away away from Earth was to go out, how long would it take for us to know that this had happened? Light travels at a speed of 3 x 10^8 meters/second. 2. What would the density be (in g/cm^3) of a block that is 4 cm by 15 cm by 12 cm, and has a mass of 4.3 kg? 3. An ob

Mass Balance Problem

Please see the attached file for full problem description. --- Q1. Starting with a pulp with a water content of 99%, how much water must be removed to obtain one ton of paper containing 60% water? Solution. Water removed Pulp

Molarity

5. Calculate the sodium ion concentration when 60.0 mL of 6.0 M sodium carbonate is added to 30.0 mL of 1.0 M sodium bicarbonate.

Solubility Product and Solubility

The solubility product of silver chromate, Ag2CrO4, at 25 degrees Celsius is 4.05 x 10^-12 mol^3/L^3. Calculate the solubility of silver chromate in: a) pure water b) 0.0500 M silver nitrate solution c) 0.0500 M potassium chromate solution

Calculating concentration in a solution

A student pipets 20.00mL of 0.030M Na2SO3 soln. into a large beaker. To this same beaker the student adds 30.00 mL of 0.020M KIO3 soln. and 50.00 mL of distilled water. The student mixes it thoroughly with a stir rod. Calculate the concentration of Na2SO3 and KIO3 in the new solution but before the reaction occurs.

Electrochemical cell

It is given that the electrochemical cell is at 298K. At time zero [Zn 2+ ]= 1.0 x 10 ^-3 M and [Ag +] = 0.500 M. Calculate the molarities of zinc and silver ions after a current of 2.00 amperes flow for 20 hours. Please show step by step and the units you are using.

Density

A cylindrical bar of gold that is 1.5 in. high and 0.25 in. in diameter has a mass of 23.1987g, as determined on an analytical balance. An empty graduated cylinder is weighed on a triple beam balance and has a mass of 73.7g. After pouring a small amount of liquid into the graduated cylinder, the mass is 79.16g. When the gold cyl

Chemistry Problems

1. The following reaction occurs: CaCO3 + 2H- -> Ca2+ + CO2 +H2O If a 25gm sample of calcium carbonate is added to a 75.5 ml HCl (density = 1.125gm/cm3, 26% HCl by mass), calculate the molarity of the HCL remaining in solution (if any) after the reaction is complete. Assume no volume change. 2. A sample of coc

Finding limiting reactant, theoretical yield, and actual yield

An electric furnace produces phosphorus by the following reaction: Ca3(PO4)2(s) + C(s)+SiO2(s)= CaSiO3(s)+CO(g)+P(I) An initial reaction mixture contains 1500g calcium phosphate, 250 g carbon and 1000g silicon dioxide. a) What is the limiting reactant? b) What is the theoretical yield of phosphorus? c) After the reaction

Determine concentrations in mixture using determinants

Please see attachment. A solvent called "mixed xylenes" contains the o-xylene, m-xylene, p-xylene and ethyl benzene. In the table below, the absorbances of each of the pure components and the absorbance of a sample of "mixed xylenes" were measured at four different wavelengths. All measurements used the same cell and, theref

Physics

Imagine that we give N2(+), O2(+) and (NO)+ ions the same velocity of 30.0 km/s and then send them into a mass spectrometer where the magnetic field strength is B=8.5MN/C. How far would the spot on the photographic plate be from the entry point for each ion, assuming that each ion completes one-half of an orbit. The atomic mas

Determine Concentration of Potassium Chromate to Use (Mohr Titration)

A titration of 0.100 M Cl^- with 0.100 M Ag^+ used an end point where silver chromate gives an orange precipitate. Select the concentration of potassium chromate that must be present so the orange-colored silver chromate precipitate will appear just when 99.5% of the chloride has been precipitated. Given: Ksp of AgCl = 1.0 x 10

Oxygen reactions

Oxygen can be preparead in a lab by the reaction: 2KCLO3 = 2H2(g) + O2(g) Question: How many grams of KCLO3 must be reacted to produce 100 g of O2?

Daltons Law of Partial Pressures

Dry air near sea level has the following composition by volume: N_2, 78.08%; O_2 20.94%; Ar, 0.93%; CO_2 0.05%. the atmospheric pressure is 1.00 atm. calculate the partial pressure of each gas in atm and the concentration of each gas in moles per liter at 0 degrees C.

Gas stoichiometry

C2H5OH burns in air: C_2H_5OH(l)+O_2 --->CO_2(g)+H_2O(l) balance the equation and determine the volume of air in liters at 35.0 C and 790 mmHg required to burn 227 g of ethanol. assume that air is 21.0 percent O_2 by volume.

the percent silver of the dime in the oxidation reaction

For my AP chemistry lab, I was supposed to find the percent of silver in a dime. I started out with the formula: Ag + NaCl → AgCl +Na. The dime was put in a covered beaker with NaCl. However, during the experiment oxygen was added as one of the reactants, accidentally. The precipitated silver chloride was obviously con

Mass percentage of sodium chloride in a mixture

A sample of a mixture containing only sodium chloride and potassium chloride has a mass of 3.5650g. When this sample is dissolved in water and excess silver nitrate is added, a white precipitate (silver chloride) forms. After filtration and drying, this precipitate has the mass 7.9143g. What is the mass percentage of sodium ch

Find the mass percent of Tl2SO4.

The thallium (present as Tl2SO4) in a 7.80-g pesticide sample was precipitated as thallium(I)iodide. Calculate the mass percent of Tl2SO4 in the sample if 0.890g of TlI was recovered.

Atomic masses: relative abundance

The element Europium exists in nature as two isotopes: 151Eu has a mass of 150.9196 amu, and 153Eu has a mass of 152.9209 amu. The average atomic mass of europium is 151.96 amu. Calculate the relative abundance of the two europium isotopes.