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    General Chemistry

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    Electron Configuration Pictorial Representation

    Write the corresponding electron configuration for the following pictorial representation. Give the full electron configuration. Name the element, assuming that the configuration describes a neutral atom. HINT: Checklist: •Be sure to format your answer correctly, using lowercase letters and superscripted numbers whe

    Measuring Electrostatic Potential Energy

    Two particles with charges q1 and q2 are separated by distance d. Rank these scenarios according to the magnitude of the electrostatic (coulombic) potential energy. Ignore sign. Scenario 1: q1 = +4 q2 = -4 d = 4 A Scenario 2: q1 = +1 q2 = -1 d = 1 A Scenario 3: q1 = +1 q2 = -1 d = 3 A

    Calculate the atomic weight of rubidium

    Rubidium has two naturally occurring isotopes with the following masses and natural abundances: Isotope Mass Abundance Rb-86 85.9118 72.15 Rb-87 86.9092 27.85 Calculate the atomic weight of rubidium. Please explain in details.

    Sodium Nitroprusside

    This posting explains the chemistry, structure and chemical properties of sodium nitroprusside. The uses of this compound in medical science and analytical chemistry are discussed.

    Sodium Atoms and Configurations

    See the attached file. Consider the Na atom. Although the ground state of Na atom has one and only one corresponding electron configuration, other electron configurations are certainly possible for Na atom; they correspond to higher-lying excited electronic states. The table below gives some of the possible electron configura

    Hamiltonian and electron configuration

    What is the Born-Oppenheimer electronic Hamiltonian for the H_2^+ cation (atomic units only)? Write down the electron configurations for C2 and F2. What is the bond order for each? Which one is likely to have larger bond dissociation energy? Which one is likely to have a longer bond length?

    Spatial Orbitals and Electron States

    In terms of one-electron integrals h and two-electron integrals J and K over spatial orbitals, what is the Hartree-Fock energy of the Be atom? For the purposes of this problem, label your one- and two-electron integrals using subscripts corresponding to the relevant orbitals (i.e., write your answer in terms h_1s,? h?_2s,J_(1s

    Lowest Energy State

    Attached is a problem involving lowest energy state in 3D. I am confused on how to 3D box and energy. Given a particle of mass in a 3D box ( ), compute the average values of the position, position, and position if the particle is in its lowest-energy state.

    Finding De Broglie wavelength for variuos scenarios

    We use Use the De Broglie wavelength formula, ohr radius definition and wave-particle duality equation to compute the wavelength of a) an electron in the n = 1 Bohr orbit of the H atom; b) an electron in the n = 2 Bohr orbit of the H atom; c) an He atom moving at 1200m/s d) an automobile (1500 kg) moving at 60 mph

    Emission Spectrum and electrons rejected

    I have attached two physical chemistry problems. The first deals with converting wavelengths to frequencies and the second deals with electrons being ejected. I am a little confuse on how to approach these problems. If you would include all work and a complete explanation it would be greatly appreciated. I will try to apply

    General Chemistry Calculations

    Hello, I need assistance with the following question, would appreciate it if someone can help me. I have defined both terms, so i just require assistance with the calculation. Thank you Question: 1. The TLV for carbon monoxide is 35ppm. Define the terms TLV and ppm and calculate them for the following example:

    Vibrational and pure rotational transitions

    HI has a force contents of 314 Nm^-1 and a bond length of 160.92 pm. Calculate the frequency of the light corresponding to the lowest energy pure vibrational and pure rotational spectrum. In what regions of the electromagnetic spectrum do the transitions lie?

    Hybridization and Dilutions/Solutions

    1) What hybrid orbital would be expected for the central atom in each of the following: ? Draw the molecular structure of these compounds and label Ï? and Ï?bonds. A: SrCl2 B: NO2 C: COF2 D: GeCl4 E: PBr3 2) Draw the possible isomers of SO3 ). 4) Prepare 25 gm of 2.5% w/w NaCl solution 5) Prepare 50 ml of 13% alcoho

    Determine the LD50 of sarin

    The lethal inhalation dose of sarin for a 200lb person has been determined to be 0.0015 mg. Determine the LD50 of sarin that researchers used to calculate this lethal inhalation dose. A. 1.4 x 10-4 mg/kg B. 0.16 x 10-4 mg/kg C. 1.8 x 10-5 mg/kg D. 0.00023 mg/kg

    Concentration of CO

    Carbon monoxide concentration in a car's exhaust is approximately 8% by volume when the car is idling (per the textbook). What is 8% in ppmv (by volume)? Answer A 800 B. 8,000 C. 80,000 D. 800,000

    Atomic Nuclear Decay

    Discuss in detail, one way in which atomic nuclear decay takes place. What is the significance of atomic nuclear decay? Analyze the societal implications of using this process. Any reference will help. Thank You!

    Measurement uncertainty

    Every measurement has a measurement uncertainty. Discuss how precise and accurate measurement can be achieved in spite of the inherent measurement uncertainty. You could use the option given below. Take a ruler and measure the height of the textbook three times. Record the three measurements, and discuss the uncertainty in


    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

    Protection from Radiation

    The best means of personal protection from radiation for emergency responders is the implementation of three basic principles: time, distance and shielding. Please show your work when answering the following questions: a. Using the inverse square law of radiation, what Geiger counter reading would you get for a radioactive m

    Significant Figures with Calculations

    How do you find correct significant figures when performing calculations? (note: the explanation will assume you know what significant figures are and can find how many significant figs are in each number) Perform these calculations, using correct sig figs (2.795m*3.10m)/6.48m 3.708 + 3.2 1.4567473*0.1.

    Writing Chemistry Equations

    1. Calculate the pH at the equivalence point in a titration between 10.00 mL of acetic acid(0.100 mol/L) and sodium hydroxide (0.100 mol/L). 2. A reaction was carried out in an acidic medium. The equation for the reaction was given as Fe 3+(aq) + HSCN(aq) <----> FeSCN 2+(aq) + H+(aq). Write the equilibrium constant expressio

    Chemical Bonding and States of Matter

    Please help with the 6 questions below. 1. The structural formula for ethanol, the alcohol in alcoholic beverages. Give the total number of: H H | | H -C - C - O - H | | H H (a) valence electrons, (b) single bonds, and (c) bonding pairs of electrons. How many extra pairs of electrons are le

    Balance Chemical Equations: Example Problems

    I need help balancing the following chemical equations. (using whole number coefficients) (note that the numbers I have indicated should be subcript) k2Cr207 + h20 + S ----> SO2 + KOH + cr203 CuO + NH3 ----> H20 + Cu + N2 NH4CL + Ca(OH)2 ----> CaCl2 + NH3 + H20 NH3 + 03 ---> N205 + H20 C6H6 + 02 ---> CO2 + H20 As2O3 +

    Isotopic in Decay Sequence

    Hello - I need some help! I need to track the nuclear decay of Thorium-232 by writing progressive nuclear decay equations until the last decay product is NOT radioactive. I also need to determine whether or not ANY of the isotopes in this decay sequence are usable in brachytherapy, and which would be best.

    Translational Partition Function

    I am interested in a step by step solution, to familiarize myself with this type of problem. The quantum mechanical energy of a particle confined to a rectangular parallelepiped of lengths a, b, and c is... Please see the attachment for full problem description.

    Neutron Number Compared to Protons

    Q1: why does the number of neutron increase after the element Iron "Fe" as compare to proton? "while element 1 through 56". Q2: Up to Iron "Fe", the number of proton and neutron are about equal, after Fe the number of neutron began to rapidly increase, with respect to the number of proton, why?