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General Chemistry

Calculating Delta H, S, and G

Use the data sheet to calculate Delta H, Delta S and Delta G at 25 degrees Celsius for each of the following reactions. In each case show that Delta G- Delta H-T Delta S. 1. Ni(s) + Cl2(g) --> NiCl2(s) 2. CaCO3(s, calcite) --> CaO(s) + CO2(g) 3. 2CH2OH(l) + 3O2(g) --> 2CO2(g) + 4H2O(l) Please see the attached docu

Polarity, bond dissociation energy of molecules

Detailed answers & explanations would be great. If hand written please do not write in cursive for I have trouble reading it. 1. Using Lewis (electron-dot) structures, explain why the ClF3 molecule is polar and the BF3 molecule is not polar. 2. For the following questions refer to the following diatomic species. (A) Li2

Seeing a Lightbulb and the Attraction of an Electron to a Nucleus

We can draw an analogy between the attraction of an electron to a nucleus and seeing a lightbulb-in essence, the more nuclear charge the electron "sees," the greater the attraction. 1. Within this analogy, discuss how the shielding by core electrons is analogous to putting a frosted-glass lampshade between the lightbulb and you

Chemistry Study Questions

1. What scientific principle or law is used in the process of balancing chemical equations? 2. In balancing equations, why should you not change subscripts in chemical formulas? 3. Define the terms limiting reactant and excess reactant. 4. Why are the amounts of products formed in a reaction determined only by the amount of

Sorting into Isoelectronic Groups

Question: Sort these species into isoelectronic groups. It doesn't matter which group goes in which box, so long as the correct species are grouped. He, Li+, O^2-, Rb+, Se^2-, F-, Be^2+, Y^3, Mg^2+ HINT: Use a periodic table to determine the atomic number of the atom. For example, xenon's atomic number is 54. A neut

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

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:

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

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

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

Mutations

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

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.

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

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?

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

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

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