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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.

6 molar solubility

The Ksubletterssp for silver(l) phosphate is 1.8x10^-18. Calculate the molar solubility of silver phosphate. show all work and all steps. thanks

Determine how many moles are used.

In the laboratory you are instructed to add 2 drops of 0.15 M AlCl3 to 2 drops of 0.15 M NaOH. If twenty drops makes one milliliter, determine how many moles of AlCl3 are used. How many moles of NaOH are used?

Determining amount of chemical consumed

The combustion of butane in oxygen at 25 celsius to form water and carbon dioxide follows the chemical reaction: 2 C4H10(gas) + 13 O2(gas) = 8 CO2 (gas) (the = is supposed to be a forward arrow) The reaction is carried out in an excess oxygen atmosphere, and 1585 kJ heat is released. Determine the amount of butane consumed.

Chemical Formula for Indium

At one time, it was thought that indium formed a chloride of formula InCl2. More recent work shows that the compound in question is actually In3[In2Cl9]. Determine the percentage by mass of indium according to each formula, and explain how the error could be made.

Ethane Combustion Problem

Ethane (C2H6) is burned with oxygen to form carbon dioxide and water. One hundred moles of each reactant are fed into a combustion chamber. Determine: (a) The stoichiometric ratio of O2 to C2H6. (b) The limiting reactant. (c) The percentage by which the other reactant is in excess.

Mass equation

Write the mass equation constant expression, K (subletter c) for the following reaction. Fe2O3(s) + 3H2(g) = 2Fe(s) + 3H2O(g) The equal sign is actually arrows pointing to each side of the equation.

Balancing Equations and Limiting Reagents

Using the initial concentration and volumes, how does one calculate the limiting reagent in each reaction below? {Please provide step by step solutions) 1# [0.1M]Pb(NO3)2 + [0.1M] Na2CrO4 --> ? initial volumes: 0.5 ml & 1 ml consecutively. 2# [0.1M]Pb(NO3)2 + [0.3M] Na3PO4 --> ? initial volumes: 1.5 ml & 0.25 ml con

Mass %

The mass% of a compound is 76.71% C, 7.02%H, and x%N. Find %xN. 2) Find empirical formula of compound. Please do step by step solutions with answer please.

Equivalent weight

Please help me solve the problem in the attachment. First of all, I don't understand exactly what equivalent weight is. Secondly, I know that the coefficient of variation is CV = (s/x) x 100% So, what does the % analyte formula in the problem statement have to do with anything? Thanks.

Calculating moles and atoms

1) A softdrink has 70.0mg of aspartame. (nutrasweet) a) Calculate number of moles of aspartame and (b) calculate number of atoms of carbon.

Molarity and Molality

The density of a 20.3 Molar CH3OH (methanol) solution is 0.858 gram/ml. What is the molality of this solution? H20 is the solvent. Show work and thanks for your help and time.