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General Chemistry

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

Frequency and wavelength

Excited mercury atoms emit light strongly at a wavelength of 436 nm. What is the frequency of this radiation?

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

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

[Pb 2+] and [I-]

If a small sample of pure PbI2 is shaken with water to produce a saturated solution, What must be the relationship between [Pb 2+] and [I-] in that solution? Refer to equation below. PbI2 (s) <--> Pb^ 2+ (aq) + 2I (aq)

Density

What is the pressure, in atmospheres, that is exerted on a diver at a depth of 166 M? Assume the density if water is 1.00g/mL. A. 0.218 B. 12.2 C. 1720 D. 0.0161 E. 16.1

Value of Kb

The [OH-] = 1.3 x 10^ -6 M for a 0.025 M solution of a weak base. Calculate the value of Kb for this weak base. a) 5.2 x 10 ^ -5 b) 3.1 x 10 ^ -7 c) 7.7 x 10 ^ -9 d) 4.0 x 10 ^ -8 e) 6.8 x 10 ^ -11

Packing of Particles in Solids-space Lattices

Hexagonal Closet Packaging vs. Cubic Closet Packaging (face-centered) vs. Body-centered a) Which of the three types of packaging has the least efficient arrangement of atoms? Justify the answer. b) How do the two more efficient forms of packing compare regarding volume? c) What is the relationship between coordination n

Chemical Bonding: Melting Point

1. Consider the following data: expect a BeF2 molecule to be linear but an SF2 molecule to be angular. Solubility in Water Melting (kg/kg H2O, 25oC) Point (oC) NaF 0.042 988 NaCl 0.357 801 NaBr 1.16 755 Nai 1.84 651 a) Explain the decreasing melting point from NaF to Nai. b) Explain th

Chemical Bonding

1. Consider you would expect a BeF2 molecule to be linear but an SF2 molecule to be angular. 2. a) How would you designate the hybrid orbitals formed by "mixing" one d one s and two p orbitals? b) How many of the hybrid orbitals would be formed by the mixing? 3. Explain why C20H40 is a solid at 25oC, while C4H8 is a gas

Descriptive Chemistry

1.Write equations for the neutralization reactions that result in the formation of the following salts: a) lithium carbonate b) copper (II) chlorate c) aluminum sulphate d) ammonium iodide 2.For each of the following situations, identify those for which a reaction is likely to occur. For those that do occur, write a net

Molecular Formulas of Different Compounds

1. A compound containing titanium (Ti) and chlorine is analyzed by converting all the titanium into 1.20g of TiO2 and all the chlorine into 6.45g of AgCl. What is the simplest formula for the original compound? 2. Estrone is a female sex hormone that is known to contain 80.0% carbon, 8.2% hydrogen, and the remainder oxygen. I

Chemistry language

Can you please assist me with these problems? 1.Write the correct formula for each of the following manganese (II) iodine 2. Write the correct formula for each of the following ions flourate 3. Name the following compounds: a) BaHPO3 b) AgIO 4. Balance the following equations: i)PbCl2+AgNO3 &#8594; AgCl+

Diameter of an Oil Droplet in Scientific Notation

A drop of oil volume 0.05 cm3 is released from a medicine dropper on to a calm surface of a pond where it spreads out to cover an area of 40 cm2. Assume that the oil has a uniform thickness equal to the diameter of an oil molecule, calculate the diameter of an oil molecule, and express answer in scientific notation with the corr

Chemistry Questions: Gases and Gas Reactions

A balloon contains 400cm3 of helium at 25 degrees and 1 atm pressure. If the balloon bursts when the volume exceeds 800cm3: a) What would be the maximum temperature it could withstand at constant pressure? b) What would be the minimum pressure it could withstand at constant tempersture? c) What height above sea level would

Life of Earth

Pretend you are an atom. Take the number of your birth month (October) as your atomic number. Determine the configuration of electrons in your valence shell and see how you might interact with the other "atoms" in your group to form ions or new molecules.

Food Chemistry and Reactions

1. What unusual aspect of water is responsible for it unique characteristics as both a liquid and as a solid? Give examples of how this property of water would affect food systems during processing. 2. The value of ∆G tells use what about chemical reactions? Give three situations and examples. 3. Chemical potential (μi)

Chemistry Notation Questions

A) Provide the type of measurement (volume, length, temperature etc.) for the following units: i) 298 K ii) 65 mL iii) 15 m iv) 290 kg v) 50 g b) Write the following measurements in scientific notation: i) 150000000 kg ii) 0.28 L iii) 0.00004 m c) Answer wheth

Lewis Structures and VSEPR (valence shell electron pair repulsion)

Lewis Structures and VSEPR (valence shell electron pair repulsion). See attached file for full problem description. 1. Listed in the attached document are electron dot formulas for several simple molecules and ions. All valence electrons are shown; however, electrical charges have been omitted deliberately. Which of the

Observation of a precipitate

Will a precipitate be observed if .10 mol Ag+ and .001 mol SO4^2- are added to make 1.0L of solution? (KSP= 1.4*10^-5)

Lennard-Jones Potential

Potential energy of a diatomic molecule is given by the Lennard-Jones potential, where A and B are constants. Find in terms of A and B, (a) the value r0 at which the energy is minimum and (b)the energy required to break up a diatomic molecule.(c) Evaluate r0 in meters and E in electron volts for the H2 molecule. In the caluculat

Sigma (σ) and pi (π) bonds

1. How many sigma (σ) and pi (π) bonds are in each of the following molecules? Molecule Number of σ bonds Number of π bonds Molecule Number of σ bonds Number of π bonds CO2 XeF3+ N2 Cl2CO CO32- ion BrO3_ 2. An iron atom is located in a molecule called an "iron-porphyrin" (or "heme") which has an import

Mayonnaise Water and Salt in Water

1. Is the mayonnaise water soluble? 2. While making rice, a housewife adds too much salt to a pot containing rice and water and then brings the pot to a boil. Immediately realizing her mistake she decides to add more water to the pot believing this will remedy the mistake. What do you think? Will her mistake be rectified by a