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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

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

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

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?

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. _______________________________________

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

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

Lyman Series for H

The Lyman series in the hydrogen atom corresponds to transitions that originate from the n=1 level in absorption or that terminate in the n=1 level for emission. Calculate the energy, frequency (in inverse seconds and inverse centimeters), and wavelength of the least and most energetic transition in this series.

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?

Molecular Geometry and Bond Order Problems

1) What is the molecular geometry of the ammonium ion? 2) What is the molecular geometry of the SO2Cl2 molecule? 3) What is the approximate F-S-F bond angle in sulfur hexafluoride? 4) What is the hybridization of the central atom in COCl2? 5) What is the hybridization of the central atom in selenium tetrabromide?

Light and Quantum Numbers

1) What is the molar concentration of a solution that is made by dissolving 6.30g of sodium chloride and diluting 1.00L?Report your answer to three significant figures. 2) In an experiment, 6.00g of Mg(s) was reacted completely with O2(g) to form MgO(s) and 148.5kJ of heat was evolved. What is the molar emthalpy of formation

Assorted General Chemistry Problems

1) In a combustion analysis, 2.00mg of vitamin C yielded 3.00mg CO2 and 0.816mg H2o. From mass spectrometry, it was found that the molecular weight of vitamin C is 176amu. Determine the mass composition of vitamin C, its empirical formula, and its molecular formula. 2) What is the energy of the photon that is emitted when the

Time for Radio Signal to Travel from Saturn to Earth

In June 2004, the Cassini-Huygens spacecraft began orbiting Saturn and transmitting images to Earth. The closest distance between Saturn and Earth is 746 million miles. What is the minimum amount of time it takes for the transmitted signals to travel from the spacecraft to Earth?

Radius/Density From bcc and fcc Unit Cells

Krypton crystallizes as a fcc (face centered cubic unit cell) having an edge length of 559 pm. (a.)What is the density of solid Krypton? (b.) What is the atomic radius of a krypton atom? (c.)What is the volume of one krypton atom? Potassium crystallizes in a bcc (body centered cubic unit cell) structure. The atomic radi

Fission and isotopes

1a.) You have 16 electrons, 16 protons, and 16 neutrons. You can combine them to make 8 Helium (He-4) atoms, 4 beryllium atoms (Be-8), 2 oxygen atoms (O-16), or one sulfur atom (S-32). What will you do to make the most stable product? Info: H-1 1.00782505 amu He-4 4.0026033 amu Be-8 8.0053052 amu O-16

solubility of PbBr2 in various solutions

If the solubility product of PbBr2 is 8.9 x 10^(-6). What is the molar solubility: (A) in pure water? (B) in 0.12 Molar KBr solution (C) in 0.18 Molar Pb(NO3)2 solution

Isotope GA-67

1. The isotope GA-67 is used medically to scan for various tumors. a.) Write the nuclear symbol for Ga-67 b.) How many protons are there in the nucleus? c.) How many neutrons are there? d.) Calculate ΔE in kJ when 1.00 of Ga-71 (nuclear mass of 70.9476 amu) is bombarded by an α-particle producing As-72 (nuclear mas

Chemistry Expressions

1. (a) Express 50 days in seconds (b) Convert 3.75 meter/sec to km/hr. Express the results in scientific notation. 2. Perform the following operations and express the answer with the appropriate number of significant figures. 863[1255-(3.45*10.8)] 3. The recommended dose of Elexophyllin (a drug used to treat