Explore BrainMass
Share

Stoichiometry

Combustion Reactions - Thermochemistry

1. A boiler burns fuel which has the following composition by mass: 82% carbon, 5% hydrogen, 6% oxygen and 7% ash. (a) Find the stoichiometric A/F ratio. If the dry analysis of the products yielded the following composition by volume: 13.2% carbon dioxide, 1.5% carbon monoxide, 6.8% oxygen and 78.5% nitrogen, calculate:

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

Solids

Lead has an atomic radius of 175 pm and crystalizes in a face centered cubic structure. Find the mass of the unit cell in grams, the volume of the unit cell in cubic centimeters, and the density of the lead in g/cubic centimeters? I submitted this problem last night and I do not understand how you are getting the measurement

Mass, Volume and Density of unit cell of lead

Lead has an atomic radius of 175 pm and crystallizes in a face centered cubic structure. Find the mass of the unit cell in grams, thje volume of the unit cell in cubic centimeters, and the density of lead in g/cubic centimeters?

Particulates breathed in per day

If a person breathes in 20m^3 of air per day and the air contains 263 micrograms of particulates per m^3, how many grams of particulates does a person breathe in per day?

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?

Mole and Weight Percent Composition

Gas chromatographic analysis of a mixture of organic compounds gave the following peak areas (sq cm): hexane = 2.7; heptane = 1.6; hexanol = 1.8; toluene = 0.5. (a) Calculate the mole percent composition of the mixture. Assume that the response of the detector (area per mole) is the same for each component. (b) Calculate t

Percentage AL and NH4AL(SO4)2 a Sample Before Filtering

The aluminum in a 1.200-g sample of impure ammonium aluminum sulfate was precipitated with aqueous ammonia as Al2O3*H20. The precipitate was filtered and ignited at 1000 degrees C to give anhydrous Al2O3, which had a mass of 0.1798g. a) What is the percentage of Al in the original sample? b) What is the percentage of NH4Al(

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.

Dehydrated Ethanol Reaction

At intermediate concentrations of H2S04 in the temperature range 140-170 degrees C, ethanol may be dehydrated by two different independent reactions (see attachment). Suppose that 30% of the ethanol reacts via reaction (1) and 70% via reaction (2). How many moles of water are produced per mole of original ethanol?

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.

Write the Mass Equation Constant Expression

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 % of a Compound

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.

Crystalline Solid Structure

Calculate the radius of a vanadium atom, given that V has a BCC (Body-centered cubic) crystal structure, a density of 5.96 g/cm^3, and an atomic weight of 50.9 g/mol.

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.

Close packing in an FCC lattice

Potassium bromide, KBr, crystallizes like NaCl in a face centered cubic lattice. The ionic radius of K+ is 133 pm and the ionic radius of Br- is 195 pm. Assuming that all Br- ions are positioned in the face and corners of the unit cell, while the K+ ions are positioned along the edge alternating between anions, calculate the l

Molarity and Molarity of Methanol

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