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# General Chemistry

### Full Ionic and Net Ionic Equations

Write the ionic and net ionic equations for the following reactions. a) AgNO3 (aq) + Na2SO4, (aq)-----> B). BaCl2 (aq) + ZnSO3 (aq)-------> C). (NH4)2CO3 (aq) + CaCl2 (aq)------>

### Geometric Structure and Localized Bonding Models

Geometric Structure and Localized Bonding Models (also as attachment) 1. For each of the following chemical species: (i) write acceptable Lewis structures (including major resonance contributors and indicating formal charges); (ii) designate oxidation states for all atoms; and (iii) draw the stereochemical structures predi

### Ionic, polar covalent and non-polar compounds

How do you tell if a compound is ionic, polar covalent, or non-polar? Find out for these compounds (Big numbers are used to represent the number of atoms because they are all 1 molecule.) a) Na2SO4 b)KOH c)(NH4)2SO d) C6H14 e)C2H5OH f)H20

### Ksp and Solubility: Concentrations of Ions in Solution

What are the concentrations of each of the ions in a saturated solution of PbBr2, given the Ksp of PbBr2 is 2.1 x 10^-6? I get stuck in solving this question when I get to the equation 4(x^3)=2.1 x 10^-6 and I don't know how to get to the answer x = 8.07 x 10 ^-3 M which is supposedly the concentration of Pb 2+. Real

### Standard Deviation : Variability of Data. A data set is presented, and the standard deviation must be calculated.

The standard deviation of a data set is a measure of the 'spread' of a distribution of data or other numerical values; it is a measure of variability within a particular data set. To calculate standard deviation of a sample, generally the variance of the sample is first calculated. The variance is the average squared deviation o

### 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 (C&#8322;H&#8323;N): 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

### General Chemistry - Effective Nuclear Charge - explanation, definition, application

Briefly explain the term effective nuclear charge and give one possible application of this concept.

### Chemical Formula for Copper Phosphate and Lead Chloride

What is the correct formula for: copper (II) phosphate lead (IV) chloride.

### Reaction Balancing Coefficient of Equation

What is the coefficient of H2O when the following equation is properly balanced with smallest set of whole numbers? ___Al4C3 + ___H2O > ___Al(OH)3 + ___CH4.

### Calculating the Pressure of Gas Sample in a Manometer

In a manometer the mercury level at the open end of the tube is 215 mm higher than at the closed end of the tube. If the atmospheric pressure is 1 atm, what is the pressure of the gas sample in units of torr? A)1.28 torr B)545 torr C)975 torr D)215 torr

### Alkanes and Boiling Points

Which of the following shows the alkanes in correct order from lowest to highest boiling points? A) hexane, pentane, butane, propane, ethane, methane B) hexane, ethane, propane, butane, pentane, methane C) methane, ethane, propane, butane, pentane, hexane D) metane, ethane, propane, pentane, butane, hexane

### a short half-life explanation

If it takes 10.0 minutes for 5000 atoms of a radioactive isotope to decay to 2500 atoms, how many of the original 5000 atoms remain after 30.0 minutes?

### Ozone Layer - What it does

1. How does the ozone layer protect the earth from ultraviolet radiations? 2. What steps need to be taken to contain the depletion of the ozone layer?

### concentration of NaCl solution after dilution

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

See the attached file. 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 and Hexane - Why Different Boiling Points

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.

### Computing the Solubility of Copper Sulfide

Work out the solubility of copper (II) sulfide. Take it that 1 litre of the mixture weighs 1 kg (in g/100g). CuS (s) <----> Cu^2+ (aq) + S^2- (aq) Ksp = 8.7 x 10^-36

### [Pb^2+] and [I^-] in the 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)

### compute solubility product Ksp

An AB2 salt has a solubility of 267 mmol/100g. Assuming that 1 L of solution weighs 1 kg. Compute solubility product Ksp.

### 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.

### States of Matter/Gas/Motion/Force

How do you think the motion of molecules in a gas (at rest) would differ from the molecules in a tornado? Why does the same amount of liquid when left in a wider and flatter container evaporate quicker than when left in a narrower and deeper container?

### 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