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mixture solution

If you have a 2 M stock solution of Tris Buffer, a 0.5 M stock solution of Magnesium chloride, and a bottle of crystalline sodium chloride. Use these reagents to make 500 ml of a solution containing 50 mM Tris, 5 mM of MgCl2, and 0.25 M sodium chloride.

Calculating moles

How do you calculate the number of moles of MgCl2 in 15g of MgCl26H2O?

Concentration of Glucose in Blood

On average, glucose makes up about 0.10% of human blood, by mass. What is the approximate concentration of glucose in blood in milligrams per deciliter?

Mass Percent

What is the mass percent of solute in each of the following solutions? a.) 155 mg NaCl/g solution b.) 0.242 L methanol (d= 0.791 g/mL)/kg water c.) 3.8 L ethylene glycol (d= 1.114 g/mL) in 6.5 L propylene glycol(d= 1.036 g/mL)

Mole fraction in a solution

What is th mole fraction of naphthalene, C10H8, in a solution prepared by dissolving 32.8 g C10H8(s) in 314 g C6H6(l)? (Use correct significant figures.)

Finding the Molality and Molarity

An aqueous solution is prepared by diluting 3.30 mL acetone, CH3COCH3, (d=0.789 g/ml) with water to a final volume of 75.0 mL. The density of the solution is 0.993 g/mL. What are the molarity and molality of acetone in this solution? (Use correct significant figures.)

Graham's Law and Stoichiometry Problems

Question #1 C2H2Br4 + 2Zn ----> C2H2 + 2ZnBr2 How many grams of ZnBr2 are produced from 125g of C2H2Br4? Formula Weights are, H=1.01 C=12.0 Zn=65.4 Br=79.9 Question #2 Which gas molecules diffuse faster, NH3 (ammonia) or C3H8(propane)? Why? Whose Law is applied here?

Concentration of Solution

Calculate the final concentration if a) 1.50L of 2.00 mol/L LiCl, 2.00L of 1.50 mol/L LiCl are mixed b) 1.50L of 2.00 mol/L LiCl, 2.00L of 1.50 mol/L LiCl and 4.00L of water are mixed. Please show work.

25 Empirical Formula, Stoichiometry and Redox Problems

1.)A hydrocarbon has the formula C12H20. 61.51 g of it are burned in the presence of excess pure oxygen gas. How many grams of water are produced in this combustion? Use these atomic weights: 12.01(C), 1.008(H), and 16.00(O). 2.)How many mL of water are needed to dilute 32.07 mL of a solution 1.53 M in HCl to 0.154 M HCl

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

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

Chemical Reaction

What volume of 0.5 M H2SO4 is needed to react completely with 20.0 ml of 0.4 M LiOH?

Titre Calculations and Reactions

1. 20.0ml of calcium lactate solution was diluted with 30ml of water, to give a titre value of approximately 20ml of 0.05M disodium edetate. What would you expect the approximate titre value to be if the calcium lactate had been dissolved in 60ml of water? 2. How many moles of disodium edetate react with each mole of calcium

Energy Required to Produce

9. Find the energy required produce 1kg of Al from native Al2O3 and compare this with the energy required to melt 1kg of aluminum in a recycling plant.

If 42.50 ml of solution of 100grams

If 42.50 ml of solution of 100grams of potassium chromate per liter was used to completely react with a sample of 10 grams of soluble lead (II) salt, what is the percentage of lead (II) in the sample

Making a Buffer

How would I make a 10% NaCl 100ml buffer made up from a 5M NaCl stock solution. The NaCl stock is aqueous solution.

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 %

Iron Production in a Reaction

How many grams of iron can be produced from 3.50 Kg FeO3 from the following reaction FeO3(s) + 3CO (g)-------->2Fe (s) = 3CO2 (g)

Anaerobic Respiration with Ethanol

If the Density of Ethanol is 0.789 g/ml, Starting with 1.00 Kg of glucose, what is the maximum amount of ethanol in grams and liters that can be obtained by the process of the following reaction C6H12O6 (I)__----> 2 C2H5OH (I) + 2 CO2 (g)

Mole Ratio

When the following equation is balanced, what is the mole ration of H2O to Be3N2? Be3N2 + H2O --> Be(OH)2 + NH3

Benzene and bromine react from bromobenzene

Benzene and bromine react from bromobenzene, as represented by the equation. The densities of benzene and bromobenzene are 0.879 g/ml, respectively. How many mL of bromobenzene can ce prepared from 12.5 mL benzene? C6H6 + Br2 --> C6H5Br + HBr