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# General Chemistry

### Molar solubility in different solutions

The solubility product of PbBr2 is 8.9 X 10^(-6). Determine the molar solubility in the following. (a) pure water I got the correct answer of 1.3e-2 M (b) 0.14 M KBr solution I got close to the right anwser with 6.4e-5 but im not sure where i am going wrong. (c) 0.18 M Pb(NO3)2 solution

### Ion consentration in saturated solution

Calculate the concentration of ions in the following saturated solutions. [Al3+] in Al(OH)3 solution with [OH -] = 2.6 10-9 M I have tried: 1.3e-30, 2.3e-25, 6.9e-25, and 8.7e-10... im stuck and i cant figure out the correct solution.

### Magnesium hydroxide

What form is found in the least amount in magnesium hydroxide and why? would it be the dissolved but non-ionized mag hydroxide.... the dissolved and separated ions or the solid and undissolved mag hydroxide

### Balance chemical equations

I thought if someone showed me how to do 2...with the smallest possible coefficients...I could figure it out from there, hopefully? ___S8 + ____ O2 --> _____SO3 or here's another one: Li2SO4 + _____ AlCl3 --> LiCl + Al2 (SO4)3

### Biological oxygen demand and water hardness

1.) Two determinations of the dissolved oxygen content of a 200 mL sample of water, made five days apart, gave 5.3 ppm and 2.2 ppm of dissolved O2 respectively. What is the biological oxygen demand of the sample? The following formula was given to us: BOD= mg dissolved 02 consumed/ Liter of water but I'm not sure how to conv

### Particle in a Box for State Particle

Consider a particle of mass m in a box of length a. Assume the state of the particle at time t=0 is: Where are the particle in a box stationary states with energy a. What is the probability a measurement of the energy will result in b. What is the expectation (average) value for the energy (<E>) in the state

### Spectrophotmetry Measured Absorbance

1.) The measured absorbance of a sample in a spectrophotometer is 0.704. What percentage of the incident light is being transmitted? 2.) A sample containing 0.0250 M concentration of a dye in a cell of 1 cm^2 cross section has a measured absorbance of 1.012 at 650 nm. Calculate the instrumental constant k for the spectrophoto

### Physical Chemistry Collision Theory

I have a list of terms that needs to be defined in a Physical Chemistry course. With each definition I need an example for each term, as a description to it or so term Chapter collision theory transition state theory rate constant Arrhenius equation integrated rate law rate law activation energy pseudo f

### Predicting the Polarizability of a Molecule: Example Problem

Predicting the Polarizability of a Molecule. Consider the following set of data for polarizability (a): Molecule Polarizability (×10-31 m3) CH4 24 C2H6 36.5 CCl4 107 From what I have learned, the simplest model for predicting the polarizability of a molecule is to assume that polariza

### Finding solubility of a gas using pressure

The solubility of N2 in blood at 37°C and at a partial pressure of 0.80 atm is 5.6 10-4 mol/L. A deep-sea diver breathes compressed air with the partial pressure of N2 equal to 3.6 atm. Assume that the total volume of blood in the body is 5.0 L. Calculate the amount of N2 gas released (in liters at 37°C and 1.1 atm) when the

### Calculating the effect of pressure on solubility

The solubility of CO2 in water at 25°C and 1 atm is 0.034 mol/L. What is its solubility under atmospheric conditions? (The partial pressure of CO2 in air is 0.0003 atm.) Assume that CO2 obeys Henry's law. I can't seem to get this problem correct. I believe I am to find the product of .034x.0003 which gives me 1.02e-5.

### Determining Molecular Formulas and Compounds

1. A 0.1014 g sample of purified glucose was burned to produce 0.1486 grams of carbon dioxide and 0.09 g of water. Glucose contains only C,H,and O. Determine the empirical formula of glucose. If the molecular mass of glucose is 180, what is the molecular formula of glucose. 2. A granulated sample of aircraft alloy (Mg, Al,

### Molecular Geometry for Carbon Atoms

_____1) Which atom below has 4 valence electrons? a) Carbon b) Beryllium c) Hydrogen d) Nitrogen e) None _____2) What is the correct Lewis dot structure for oxygen? a) b) c) d) e) no right choice _____3) Which chemical has the most number of valence electrons in its Lewis structure (electron-dot structure)?

### Natural and Chemical Cleaners

What is the chemical make-up of natural cleaners? How do these products compare to traditional cleaners? Are the active ingredients the same or different? How do the products differ from traditional cleaning products? Are these products safer or more environmentally friendly than traditional products?

### Boiling Point of a Solution of Ethylene Glycol and Water

11.4 L Ethylene glycol (C2H6O2), a nonelectrolyte, is added to 12.1 L of waterto produce an antifreeze solution with a freezing point of -31.5°C? (The density of ethylene glycol is 1.11 g/cm3, and the density of water is 1.00 g/cm3.) What is the boiling point of this solution? °C

### Solubility Problems

Please refer to the attachment for the complete solution. A solution contains 0.01 M Ag+, 0.04 M Hg22+ and 0.1 M Pb2+. NaCl is gradually added to precipitate the Ag+ as AgCl, the Hg22+ as Hg2Cl2, and the Pb2+ as PbCl2. Given the following Ksp values: AgCl (Ksp = 1.6 x 10-10); Hg2Cl2 (Ksp = 3.5 x 10-18); PbCl2 (Ksp = 2.4 x

### Complete balanced equation

Please provide a complete balanced equation of the combustion of the following molecules. Also, indicate all phases (g,l,s): a) CH3OH b) COCl2 c) H2NOH d) N2O4 Please refer to the attached file for the proper formatting.

### Information on dihydrogen phthalate

I try to look up information on dihydrogen phthalate, and not much information can be found through the search engines online. However I need to know if there is a balanced equation of NaOH and dihydrogen phthalate as a primary standard, and what does the structure of dihyrogen phthalate looks like.

### Calculate Wavelength, Energy

The blue color of the sky is due to the scattering of sunlight by the molecules in the air. The blue light has a frequency of about 7.5 x 10^14 Hz. A. Calculate the wavelength, in nm, associated wth this radiation. I believe the correct formula for this part is speed of light (299,792,458 m/s x 7.5 10^14 Hz). B. Calcul

### Genetic Mutation and Blood Disorders

1. Define a genetic mutation and state the types of genetic mutations. Discuss the effects of genetic mutations. 2. A thirteen-year-old girl, who is underdeveloped and thin, has a blood disorder. She frequently experiences chest and abdominal pain, fever, and coughing, and has trouble breathing. Her teachers often spend ad

### Significant Figures: Example Problem

I am trying to figure out the proper answer in significant figures for this, I'm not sure which rule I follow, the addition/subtraction rule or the multiplication/division rule? 320.5 - (6104.5 / 2.3) I'm wondering if the answer should be -2333.6 or -2379.5? Could you please show work? Thank you!

### Engine Piston Displacement: Example Problem

I am unsure of how to properly answer this question. What is the engine piston displacement in litres of an engine whose displacement is listed as 450 in.3? (inches cubed in.^3) I made an attempt at the question: 450 in.3 (16.4 cm3 / 1 in.3 ) (1 mL / 1 cm3 ) ( 1 L / 1000 mL) = 7.38 L I'm not sure if that's right

### Multiplication, Division, Adding and/or Subtracting

I understand the rules for significant figures with multiplication/division, and adding/subtracting. But I am unsure of what to do when there is both multiplication and/or division, and adding and/or subtracting in the same question? ex: (0.0045 x 20 000.0) + (2813 x 12) 90.0 + 33756 = 33846 (following BEDMAS I end up

### Gas Laws: Partial Pressure in a Mixture

Consider the flasks diagrammed below. Before opening the stopcock, the flask on the left contains 445 torrs of H2 gas and the flask on the right contains 0.190 atm of N2 gas. What are the final partial pressures of H2 and N2 after the stopcock between the two flasks is opened? (Assume the final volume is 3.00 L.) What is the tot

### Calculating Vapor Pressure: Example Problem

A 2.30 L sample of O2(g) was collected over a liquid at a total pressure of 785 torr and 25°C. When the O2(g) was dried (vapor of that liquid removed), the gas had a volume of 1.86 L at 25°C and 785 torr. Calculate the vapor pressure of this liquid at 25°C.

### Atom of Tin and Sn Molecules

An atom of tin (Sn) has a diameter of about 2.8 x 10 -8 cm. a. What is the radius of a tin atom. ? _________________Angstroms (A) and ________________m b. how many Sn atoms would have to be placed side by side to span a distance of 6.0 um? _________________________number os Sn atoms c

### Balancing Reactions

Please see the attached file for the fully formatted problems. In the real world, you do not have a program to balance equations for you. For questions 12-16 below, please fill in the first table below to indicate the initial numbers of reactant and product atoms. Balance the equation on your own and then fill in the second

### Significant Figures by Mathematical Computations: Example

Multiply or Divide the following problems. Round to the correct number of significant figures. a) (64.69)(8.08) = _____________ b) 0.7406/0.144 = ____________ c) (354.43)(4.596) = _____________ d) 345.67/9.01 = _____________

### Shape, Size, Solubility and Concentration of Particulates

Briefly describe the differences between shape, size, solubility and concentration of particulates.

### Energy of Light, Electronic Transitions, The Photoelectric Effect and Quantum Numbers

1. Energy is ____ when an n = 4 to n = 2 transition occurs when an electron adds to the H+ ion and ends up in the n = 3 shell. a) destroyed, created b) emitted, created c) absorbed, emitted d) emitted, absorbed e) emitted, emitted 2. Calculate delta(E) if 1 = 1.40 kJ and w = -658 J. a) -657 kJ b) 0.742 kJ c) 1.4