Share
Explore BrainMass

Physical Chemistry

Solutions, Solubility and Concentration

18. The chloride in a 0.12-g sample of 95% pure MgCl2 is to be precipitated... Solutions, Solubility and Concentration. See attached file for full problem description.

acid base titration.

See attached file for full problem description. 13. A hydrocholoric acid solution is standardinzed by titrating 0.4541 g of primary stardard tris(hydroxymethyl)aminomethane. If 35.37 mL is required for the titration, what is the molarity of the acid? 15. A sodium hydroxide solution is standardized by titrating 0.8592 g of

Balanced & Net Ionic Equations

Write the balanced molecular equation, complete ionic and net ionic equation for the following acid base reaction. HCL(aq) + NH3(aq) NH3 is an exception, so I'm not sure what to do with it.

Salts and Their Reactions

7. When 1.00 grams of chromium metal is heated in excess iodine, 8.301 rams of chromium iodide salt is formed. Calculate the empirical formula of this salt. 8. When a calcium carbonate tablet is ingested, it dissolves by the reaction of stomach acid, which contains hydrochloric acid. The unbalanced equation for this reaction

Analysis of Calcite Sample

The analysis of a calcite sample yielded CaO percentages of 55.95, 56.00, 56.04, 56.08, and 56.23, respectively. The last value appears anomalous; should it be retained or rejected?

What is the heat of combustion per gram of butane?

5. The combustion of butane produces heat according to the equation 2C4H10(g) + 13O2(g)  8CO2(g) + 10H2O(l) H° = -5,314 kJ What is the heat of combustion per gram of butane? A.-32.5 kJ/g B.-45.7 kJ/g C.-91.5 kJ/g D.-2,656 kJ/g E.-15,440 kJ/g 6. The freezing of water is an example of an exotherm

High-temperature equilibrium calculation

High-temperature equilibrium The data below are for the dissociation of PCl5 into PCl3 and Cl2, all in the gas phase. ? (a) What is ΔGo for the reaction at each of the five temperatures? ? (b) What is ΔHo for this reaction? ? (c) What is ΔSo for the reaction at each of the five temperatures? [Reference: A Textbook of

Percentage of Cis Isomer at Equilibrium

Consider the trans-to-cis isomerization of 1,2-dichloroethylene. If the Gibbs energy of formation is 27.34 and 22.11 kJ / mol for the trans and cis isomers, respectively, what is the percent of cis isomer present at equilibrium? You may ignore activity corrections. See attached file for full problem description.

Calculate the molar heat capacity of mercury in J/(mol degrees C).

7. It takes 585 J of energy to raise the temperature of 125.6 g mercury from 20.0 degrees C to 53.5 degrees C. Calculate the molar heat capacity of mercury in J/(mol degrees C). 8. The specific heat capacity of silver is 0.24 J/(g x degrees C). It takes 3.57 kJ of energy to heat a sample of pure silver from 12.0 degrees C

Analytical Chemistry Questions: Ionic Strength

1. A and B react as follows: A + B = C + D. The equilibrium constant is 2.0 x 10^3. If 0.30 mol of A and 0.80 mol of B are mixed in 1 L, what are the concentrations fo A, B, C, and D after reaction? 4. The dissociation constant for hydrocyanic acid, HCN, is 7.2 x 10^-10. Calculate the percent dissociation of a 1.0 x 10^-3 M s

Empirical Formula & Products

A compound of bromine and fluorine is used to make UF6, which is an important chemical in processing and reprocessing of nuclear fuel. The compound contains 58.37% by mass of bromine. Determine its empirical formula. A) BrF B) BrF2 C) Br2F3 D) Br3F E) BrF3 Magnesium reacts with iron(III) chloride to from magnesium chlo

Calculate the total cell number in the original culture

You are given a 500ml culture of Euglena from which a 1 ml sample is taken and put in 49 ml of water. Absorbance was measured on this sample but the reading was off the scale. One ml of this solution is taken and diluted in another 249 ml of water, and this time the OD675nm gave the reading of .27. If the turbidity of .27 corres

Argon Gas Specific Heat and Conduction Bands

3. Argon gas is composed of point atoms and oxygen gas is composed of linear molecules of the form O---O where O denotes an oxygen atom. Determine the ratio of the specific heats at constant volume for these two gases. 4. Describe two different ways by which electrons can move from the valence band to the conduction band.

Ideal Gas Law Questions

3. How is the ideal gas law modified to account for the finite volume of molecules? 4. The temperature of the sea bed 60 m below the surface and at the surface are both 20C. A rubber balloon is inflated at the sea bed with 2.0 mole gas neglecting the works done on the rubber determine: i)the volume of the balloon at the se

Gas Law

1.a) state the assumption associated with the model used to develop the Ideal Gas Law b) hence or otherwise describe under which physical conditions does the ideal gas law applies 2. Explain why hydrogen which has one electron in its lowest state, should in principle be a metallic conductor in its solid state whereas heli