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General Chemistry


A gas sample containing N2 and O2 was found to contain 72% N2. If the pressure of the sample was 2.0 atm, what is the partial pressure of O2? A. 0.56 ATM B. 0.28 ATM C. 1.44 ATM D. O.72 ATM E. 0.43 ATM


The pascal is the SI unit for pressure defined as force (in newtons) per unit area ( in m2). If the force exerted by a gas on a 2.5 square meter area is 8.5 newtons, what is the pressure of the gas in Pa? A. 0.29 B. 0.21 C. 8.5 D. 17 E. 3.4

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 → AgCl+

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

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

Half Life Homeowrk Problems

Is there just one formula to calculate half life problems? What is the process or formula for solving these problems. 1. A 2.5 gram of an isotope of stontium-90 was formed in a 1960 explosion of an atomic bomb at Johnson island inthe Pacific test Site. The half -life of strontium-90 is 28 years. In what year will only .625

Nuclear equations: Example problems

8. Show that for this nuclear equation, the sum of the subscripts on the left is equal to the sum of the subscripts on the right . Then show that the sum of the subscripts on the left is equal to the subscripts on the right 239 94PU + 4 2He---> {243 96 Cm} --->242 96 Cm + 1 On 9.When 4.oo g of hydrogen nuclei fuse to form he

Lewis Structure Hybridization

4. The molecule pictured below is AZT. It is a widely used drug for the treatment of AIDS. The Lewis structure below is complete except for electron lone pairs. For this structure: a. Draw in all missing electron lone pairs. b. Write in the shape of the molecule at the atoms indicated by arrows attached to boxes with "shap

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

Radial Wave Function of Hydrogen

Use the Radial Wave Function of a Hydrogen-like atom to calculate the radii of the 2 nodes of the 3s orbital in units of a0 for the H atom.

Net Ionic Equation

Zinc is reacted with lead nitrate. Balance equation and write net ionic equation.

Oil Drop Experimental Units

Please show how to solve the following problem: Repeat Millikan's oil drop experiment using a unit of your own devising (B) rather than the unit of Coulombs. You measure the charges on 4 different drops labeled a, b,c, d. You determine that drop a has charge 13.52 B, drop b has charge 3.359 B, drop c has charge 10.21 B, and

Valance Bands & Energy to Produce and Electron Hole Pair

3. A material has an effectively full valence band and an empty conduction band. Explain why that if these two bands overlap the material behaves as a metal and if they are separated by a few electron volts in energy the material is an insulator. 4. Calculate the minimum energy a photon must have to produce an electron hole p

Paramagnetic Elements

Which of the following species would you expect to be paramagnetic? Briefly explain the answers using molecular orbital energy level diagrams or molecular orbital electron configurations. N2, N2-, N2+, O2, N2^2- O2+, O2-, O2^2-

Ionic Formulas Completed

Complete the chart by filling in the correct ionic formulas. Cl- OH- O2- SO42- CO32- PO43- Na+ NH4+ K+ Ba2+ Ca2+ Mg2+ Fe2+ Cu2+ Al3+ Fe3+

Clinical Uses of Radioactivity & Decay

How long would it take for a radioactive isotope with a half life of 2 weeks to lose at least 70% of its radioactivity? Describe two clinical uses of Radioactivity.