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Stoichiometry

Atomic Mass & Isotopic Abundance

The element boron consists of two isotopes, 10(superscript), 5(subscript) B and 11(superscript), 5(subscript)B. Their masses, based on the carbon scale, are 10.01 and 11.01, respectively. The abundance of 10(superscript), 5(subscript)B is 20.0% and the abundance of 11(superscript), 5(subscript)B is 80.0%. What is the atomic mass

Stoichiometry: Sodium Iodide and Mercury Nitrate

Given that 24.0mL of 0.170 M sodium iodide reacts with 0.209M mercury(II) nitrate solution according to the unbalanced equation: Hg(NO3)2 + NaI gives HgI2 + NaNO3 a) What volume of Hg(NO3)2 is required for complete precipitation? b) What is the mass of HgI2 precipitate?

Calculate molar solubility

Calculate the molar solubility of AgCl in a solution made by dissolving 10.0 g of CaCl2 in 5.00 L os solution.

Chemical Quantities

1. The traditional method of analysis for the amount of chloride ion present in a sample was to dissolve the sample in water and then slowly add a solution of silver nitrate, silver chloride is very insoluble in water, and by adding a slight excess of silver nitrate, it is possible effectively to remove all the chloride ion from

Concentration & Mass

CaCO3 (s) + HCl(aq) --------------> CO2 (g) + CaCl2 (aq) + H2O (l) What mass of CaCO3 would you need to completely neutralize 50ml of 0.1 M HCl? Suppose a chemist mixed 2.00g of CaCO3 (s) with 100ml of 0.250 M HCl. What mass of each of the three products would form? In the question above, what is the concentration of Ca

Reactants

If I start with 2NaCl as a balanced equation, how am I able to figure out what volume of Chlorine gas measured at 20 degrees celicus, pressure of 1200mmHg, will react with 1.25g of sodium

Density

How can find the densityof carbon dioxide when its at 298K and 745 torr

Finding mass

If oxygen is in 180L tanks, at 150 atm pressure and 290K,how can i find the mass in kilgrams that is contained in each cylinder

Decomp of NaN3

How do you find the # of grams of NaN3 are needed to produce 40 L of nitrogen to fill a container to a pressure of 1.30 atm and a temp. of 28.0*C

Molar mass of gas

How do you find the molar mass of a gas .286g in a 125ml container at 60cm of Hg at 25*C?

Solving Chemical Equations

1. Formaldehyde HCHO, once used as a preservative in biology laboratories, is prepared commercially by the reaction: 2 CH3OH + O2 = 2 HCHO + 2 H2O The percent yield is 84.9% in a manufacturing plant. How much formaldyhyde can be expected from processing 397kg CH3OH? 2. A solution containing 1.63g of barium chloride is

Cobalt by Volhard

Cobalt 2+ can be analysed by treatment with a known excess of thiocyanate in the presence of pyridine according to the equation: Co2+ + 4C5H5N + 2SCN- -------> Co(C5H5N)4(SCN)2 (s) The precipitate is filtered off, and the SCN- content of the filtrate is determined by Volhard titration. Lab Results: 25ml of unknown solu

Finding the Concentration of Whiskey in m/v%

Add approximately 100cm^3 of water to 10cm^3 of whiskey - then fill up the flask to the 500cm^3 mark with water. Pipette 20cm^3 of this solution into a conical flask containing 70cm^3 of 0.05M acidic solution K2Cr2O7. Titrate the excess unreacted K2Cr2O7 with 24.82cm3 of 0.1268M Fe(II) solution. Find the concentration of the

Mole concept

(a) How many moles are there in 1.95 x 10^24 atoms of copper? (b) How many moles are there in 85.7g of H2SO4?

Solving for the De broglie Wavelength

1. a) Calculate the De broglie wavelength of a golf ball that is 100.0 g and moving at 30.0 m/s. b) Why does the golf ball look like a ball and not like a beam of light? (hint: where is the wavelength on the em spectrum)

Molar Mass

How do you figure out the mass in grams of 0.750 moles of CH3CH2OH, ethanol?

Pvnrt, etc.

Please follow instructions in the attached files.

Basic Chemistry Problems

Hi, I need some assistance understanding the answers to the following multiple choice questions: 1. The weight of a body varies according to the force of gravity exerted on the body. True False 2. An anion is the a: - Positive pole in an electrical system - Subatomic part of an atom - Molecule with a +1 net charge

Don't understand

The following reaction takes place: 2KClO3 -> 2KCl + 3O2 How many grams of O2 are produced when 175.0g of the KClO3 react?

Electronic Spectra in Coordination Chemistry

The most intense absorption band in the visible spectrum of [Mn(H20)6}2+ is at 24,900 cm-1 and has a molar absorptivity of 0.038 mol -1 cm-1. What concentration of [Mn(h20)6]2+ would be necessary to give an abosorbance of 0.10 in a cell of path length 1.00.