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General Chemistry

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.

Oil Drop

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

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.

Visible Spectrum of Hydrogen

Calculate the wavelength in nanometers of the spectral line in the visible spectrum of hydrogen for which n1 = 2 and n2 = 3. What color is this line?

MO theory and dissociation energy

Use simple MO Theory (LCAO-MO) to explain why the dissociation energy of neutral N2 is greater than the N2+ ion, but that the dissociation energy of the O2+ ion is greater than the O2 neutral.

Degrees of freedom of a saturated solution

A saturated solution of Na2SO4 with excess of the solid is present in equilibrium with its vapor in a closed vessel. Calculate the number of degrees of freedom, f, of the system. Ignore the autoprotolysis of water and assume that the salt solvates without ionizing. F = c - p +2 or use f = c-p +2 -r -a c = chem species

Calculate the Number of Moles

A steel tank with a volume of 9.583 L contains N2 gas under a pressure of 4.972 atm at 31.8 °C. Calculate the number of moles of N2 in the tank.

Finding Coefficients?

When the following equation is balanced, the coefficients of BaO2 is? _BaO2-> BaO+ _O2

AP Chemistry: Test Review

(See attached file for full problem description) --- I need full explanation of each step. Please help. 1. The helium ion, He+, has energy levels similar to those of the hydrogen atom, since both species have only one electron. The energy levels of the He+ ion are given by the equation En = - 5248.16 kj/mole n =

Percentage yields

A chemist isolates 17.43 g of product from a reaction that has a calculated theoretical yield of 21.34 g. What is the percentage yield?


A) What is an oxygenate? b) Name one octane enhancer

Chemical Symbols...

Give the name and chemical symbol for: a) An element with 50 electrons b) An element with 28 protons c) An element with 2 electrons in the first shell, 8 electrons in the second shell, 8 electrons in the third shell, and 2 electrons in the fourth shell d) An element with atomic number of 78

Compound or a mixture?

Tell whether the following is a property of a compound or a mixture: a) Can contain three elements in a specific ratio b) Varies in chemical composition depending on the sample size c) Can be classified as either homogeneous or heterogeneous