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General Chemistry

What is the molarity of lactose in milk?

On average, cow milk is 4.7%(w/w) lactose. The molecular weight of this disaccharide is 342.3g C12H22011. Assuming milk has the density of water (it is >90% water) what is the molarity of lactose in milk?

Explanation of melting point & boiling point deviations

I only need help on question 3. I have perfomed the labs for melting pt and boiling pt on the following four and only need help with question 3 acetonitrile (C₂H₃N): GIVEN MP = -45.5C, BP = 77.3C My results MP= -46.8 C, BP = 79.4 C benzene (C6H6) GIVEN

Molar solubility product of barium fluoride

Please help with the following problems. Provide step by step calculations for each. 5.[a] The molar solubility of barium fluoride, BaF2, is 7.5 x 10-3 M. Calculate the solubility product constant [b]Calculate the molar solubility of lead fluoride, PbF2 in water, Ksp = 2.7 x 10-8 6.Calculate the molar solubility of bism

Concentration of NaCl Solution

During the course of an experiment, a 0.300 M NaCl solution with an initial volume of 25.0 ml is diluted to a total final volume of 26.0 ml. What is the concentration of NaCl in the final solution? Do I use M1V1=M2V2 ?

PowerPoint Presentation on the Element Boron

BORON I am looking for someone who is knowledgeable with PowerPoint. I need help getting started with this project and knowing how to go about this. My classmates told me finding a scientific article is the hard part to this project, so I want someone to help me with that also. _______________________________________

Frequency of vibration energies

Suppose the vibration energies are given as Ev=w_e(v+1/2)-w_ex_e(v+1/2)^2 with w_e=3150cm^-1 and w_ex_e=113cm^-1. Calculate the frequency where the v=0-->v=4 overtone band occurs

Stable Molecules and Molecular Orbital Theory

1. Explain using molecular orbital theory (MO) why Na2s a stable molecule. 2. Explain using MO why Ca2 (in its ground state) is not a stable molecule. 3. Explain using MO why Ca2 (in its first excited state) is a stable molecule.

Forming Double and Triple Bonds

Explain why only certain elements can form double bonds to themselves. Why can only C and N form triple bonds to themselves?

Electrochemistry and Cell Diagram

What voltage would you measure if you set up the cell diagrammed below? (I represents a straight line up and down) Ag (s) I 0.79 M Ag^+ (aq) II 0.22 M Zn^2+ (aq) I Zn

Butane, CH3CH2CH2CH3, has a boiling point of 0.4ºC

Butane, CH3CH2CH2CH3, has a boiling point of 0.4ºC, and hexane, CH3CH2CH2CH2CH2CH3, has a boiling point of 69ºC. Both are nonpolar molecules. Explain the large difference in the boiling points of these two substances.

Concentration in a Saturated solution

A 20.1 g sample of NaI is dissolved in water to make 0.204 L of solution. The solution is then saturated with PbI2. What will be [Pb^2+] and [I^-] in the saturated solution? (in M)

Neutralization

What volume of 0.101 M HNO3 is required to neutralize 23.7 mL of 0.00517 M Ba(OH)2 mL

Finding Molar Concentration

You have a 50 µM solution of sodium phosphate. Express this as a molar concentration, as a millimolar concentration.

General Chemistry Problems

10.40) Many gases are shipped in high-pressure containers. Consider a steel tank whose volume is 65.0L and which contains O2 gas at a pressure of 16,500kPa at 23°C. a. What mass of O2 gas does the tank contain? b. What volume would the gas occupy at STP? c. At what temperature would the pressure in the tank equal 150.0atm? d. W

Assorted General Chemistry Problems

8.20) a. The lattice energies of NaF and MgO are 910kJ/mol and 3795kJ/mol. Account for the difference in these two quantities. b. Account for the difference in lattice energies of MgCl2 (2326 kJ/mol) and SrCl2 (2127kJ/mol). 8.28) Calculate the lattice energy of CaCl2. Is this value greater than or less than the lattice energ

General Chemistry Problems

5.38) Consider the following reaction: CH3OH (g) ---> CO (g) + 2 H2 (g) deltaH = +90.7 kJ a. Is heat absorbed or evolved in the course of this reaction? b. Calculate the amount of heat transferred when 45.0 g of CH3OH (g) is decomposed by this reaction at constant pressure. c. For a given sample of CH3OH, the enthalpy change

Assorted General Chemistry Problems

1.28) a. A cube of osmium metal 1.500cm on a side has a mass of 76.31g at 25°C. What is the density in g/cm3 at this temperature? b. The density of titanium metal is 4.51g/cm3 at 25°C. What mass of titanium displaces 65.8mL of water at 25°C? c. The density of benzene at 15°C is 0.8787g/mL. Calculate the mass of 0.1500L of be

Calculate the deBroglie Wavelength

Calculate the "deBroglie wavelength" for each of the following: 1. an electron moving at 0.82 times the speed of light...... in meters 2. a 125-g ball moving at a speed of 13.6 m/s.....in meters 3. a 61-kg person walking at a speed of 2.00 km/hr....in meters These answers explain why macroscopic (large) objects a

Solving 7 Chemical Equations

I desprately need help solving these chemical equations to help me to study for an exam. Rules for Solving Chemical Equations: 1. Write the chemical reaction in word form 2. Post your symbols 3. Post diatomics (for single units only) 4. Post oxidation numbers for compounds 5. Post subscription (for compounds onl

Assorted General Chemistry Problems

1) Given the following data table of average bond enthalpies, estimate the ΔH^rxn for the reactions 2H2+O2-- 2H2O Bond Average (kJ/mol) H-H 436 O=O 498 H-O 423 2) Draw eight distinct, valid Lewis resonance structures for the molecule XeO3. 3) Which structure or structures is or are mo

Assorted General Chemistry Problems

1) List the following gases in order of increasing root-mean-square speed, all at the same temperature: H2, He, O2, Ne 2) Under what conditions of pressure and temperature is a real gas most expected to deviate from ideal gas behaviour? 3) What intermolecular interactions would be the strongest between molecules CH2Cl2?