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Toxicity of TCDD in Animal Based Foods

Given that the average TEQ of animal-based foods is about 0.7 picograms of TCDD equivalent per gram, and that the LD50 for 2,3,7,8-TCDD is about 0.001 mg/kg body weight, what mass(kg) of animal-based food would you have to consume to ingest a fatal dose of it?


Im confused on how to do this problem all together. I can't find help in the book because their answers are hard to follow. If you could work this out and explain how each step was done so I could understand how to do it that would be awesome. Thank you Given that the average TEQ of animal-based foods is about 0.7 picograms o

Titration of Sulfhydryl Groups on an Enzyme

Many enzymes are inhibited irreversibly by heavy metal ions which react with essential sulfhydryl groups to form mercaptides. The affinity of silver ions (Ag+) for sulfhydryl groups is so great that it can be used to titrate -SH groups quantitatively. To a 10 ml of solution containing 10mg/ml pure enzyme was added just enough

calculation of molar concentration of salt with known Ksp

I need some clear and simple help on understanding how to calculate the molar concentration of an ion if the Ksp of the compound is known: I have 2 problems that I want to clearly understand: 1) Zinc hydroxide: --- if the Ksp for Zn(OH)2 is 1.2x10^-17 M and my solubility equation is: Ksp = [Zn] [OH]^2 --- how do I determi

SO2 Concentration Downwind from a Power Plant

4) A power plant burns 10^4 kg hr-1 of coal that contains 2.5% sulfur. The stack is 50 m high, and the plume typically rises 30 m. a) Calculate the ground-level concentration of sulfur dioxide (SO2) (in micrograms m-3) 800 m downwind from the source directly under the plume under the following conditions: Wind speed = 4 m s-1

Typical Titration/Neutralization Problems

What volume of 0.150M HClO4 solution is needed to neutralize 54.00mL of 8.80×10^-2 M NaOH? What volume of 0.120M HCl is needed to neutralize 2.78g of Mg(OH)2? If 25.0 mL AgNO3 of is needed to precipitate all the Cl- ions in a 0.785 mg sample of KCl (forming AgCl), what is the molarity of the AgNO3 solution? If 45.5

Molar concentration, solutes, and solvents

Calculate the molar concentration of a solution containing 4.75 of Ca(NO)3 in 0.200 L Calculate the volume of 2.00M Na3(PO)4 in milliliters that contains 6.80g of solute. How many grams of solute are present in 42.0mL of 0.200M K2Cr2O7 ? If 4.20g of (NH4)2SO4 is dissolved in enough water to form 400mL of solution

Find the concentration of the hydrogen peroxide solution.

Please see attached file for full problem description. 1. Find the concentration of the hydrogen peroxide solution. Doing an analysis of hydrogen peroxide using Potassium Permangate Equation is: 2KMnO4(aq)+5H2O2(aq)+3H2SO4(aq) -->5O(g)+K2SO4(aq)+2MnSO4(aq)+8H2O(l) Potassium Permangate is the titrant. Obtained a 1.00mL al

Example of Lab Report: Decomposition of Potassium Chlorate

Calculate and record the following for the experiment performed with 10.000 g KClO3 1. (a) mass of the crucible with manganese(IV) dioxide (in grams) = 53.300g (b) mass of the crucible after potassium chlorate has been added (in grams) = 63.300g (c) mass of the crucible after heating (in grams) = 59.383g (d) mass of po

Finding the Age of a Rock Using Radioactive Decay Data

(1) The half life of U-238 is 4.51x10^9 yrs. In a rock containing N atoms of U-238, how many Helium atoms are produced by radioactive decay of U-238 to Pb-206 in 4.51x10^9 yrs? (2) A rock is analyzed for its helium and uranium content and found to contain 1.00x10^-9 mole of U-238 atoms, and 2.00x10^-9 mole of Helium atoms. As

Concentration of Lead in Soil from Mine Tailings

Lead from mine tailings containing 0.6 % lead was applied at a rate of 12 metric tons per acre of soil and worked in to a depth of 20 cm. The density of the soil is 1.8 g/cm3. To what extent does this add to the burden of lead in the soil? (There are 640 acres per square mile and 1609 meters in a mile.) a) 19 ppb b) 45 ppb

Calculations required for a typical "Calculation of Gas Constant" lab report.

Example of Gas Law Constant Lab Report PLEASE SEE THE ATTACHED FILE FOR THE FULLY FORMATTED PROBLEM 1. A student performs the experiment according to the instructions in this experiment. (SHOW WORK in spaces provided) a. The weight of magnesium ribbon used is 0.0328 grams. How many moles of hydrogen could be collected

Synthesis of a chemical compound: Making alum from aluminum

How do I calculate the amount of alum left over in the following problem? Experiments show that solubility of alum in 25 mL of 1.4 M KOH plus 10 mL of 9M H2SO2 is about 1.0 g at 1.0 oC and 1.7 g at 6.0 oC. Using your measured solution temperature (4.5 oC) estimate the amount of alum left in your chilled solution

mass percent and volume percent of ethyl alcohol in solution

Ethyl alcohol, C2H6O is the alcohol present in liquor. A solution is made up by adding 25.0 mL of ethyl alcohol (d = 0.789 g/mL) to 45.0 mL of isopropyl alcohol, C3H8O (d = 0.7855 g/mL). Assuming volumes are additive, calculate the following: The mass percent of ethyl alcohol in the solution. Ethyl alcohol, C2H6O is

Calories from Fat

A person on a 2500-Cal low-fat diet attempts to maintain an intake of no more than 20% of food energy from fat. What percent of the daily fat allowance is represented by a tablespoon of peanut butter (15.0 g and 50.1% fat)? Fat has a food value of about 9.0 Cal/g. A. 14 % B. 27 % C. 2.7 % D. 0.17% E. 5.4 %


From the following reaction please calculate the grams of sulfur dioxide, SO2 produced when a mixture of 50.0 g of carbon disulfide and 72.0 grams of oxegen reacts. Which reactant remains unconsumed at the end of the combustion. How many grams remain? CS2 + 3O2 ----> CO2 + 2SO2

Mole, Empirical and Stoichiometry Calculations

Mole Calculations (Determining Avogadro's Number): 1. Calculate the mass of carbon in a diamond that contains 3.33 x 1024 atoms of C. 2. Calculate the mass of chloroform that contains 1,000,000,000,000 molecules of CHCL3. 3. Calculate the number of NaCL formula units in 1.37 g of table salt. 4. Calculate the number of N2 mo

The Production of Sulfur Trioxide

SO3 can be produced in the following two-step process: FeS2 + O2 ---> Fe2O3 + SO2 S02 + O2 ----> SO3 Assuming that all the FeS2 reacts, how many grams of SO3 are produced when 20.0 g of the FeS2 reacts with 16.0 g of O2?

Stoichiometric Relations Chemistry

The equation for one of the reactions in the process of reducing iron ore to the metal is Fe203(s) + 3CO(g) ??> 2 Fe(s) + 3 CO2(g) a. What is the maximum mass of iron, in grams, that can be obtained from 454 g (1.00 lb) of iron(III) oxide? b. What mass of CO is required to reduce the iron(III) oxide to iron metal?


A car gets 9.2 kilometers to a liter of gasoline. Assuming that gasoline is 100% octane (C8H18), which has a density of 0.69 g/cm3, how many liters of air (21% oxygen by volume at STP) will be required to burn the gasoline for a 1250-km trip? Assume complete combustion.

Balanced chemical equation for biosynthesis

Please help with the following problem. Write the balanced chemical equation for the biosynthesis of ethanol. Label the sucrose and the ethanol in the equation. If you start with one mol sucrose, how many mol ethanol is produced? (Assume complete conversion of sucrose to ethanol.) The density of ethanol is 0.80 g/ml. A

Molecular Weight by Freezing Point Depression of Solution

A 0.573g sample of a nonvolatile solute is added to 15.6g of napthalene and the mixture warmed until melted. The freezing point of the solution was determined and found equal to 78.1C. The freezing point of naphthalene is 80.2C. How do you find out if the boiling pt and the vapor pressure increases or decreases? How do you