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General Chemistry

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?

Oxygenate

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

The following are mixtures...

Tell if the mixture is homogeneous or heterogeneous and explain why you classified it as homogeneous or heterogeneous. a) Iced tea b) Salad c) Chocolate chip cookie

Volatility

Suppose you were given samples of two different liquids. Describe how you would determine which one is more voliatile.

Q (rotational) problem

Calculate the ratio of HCL molecules in the first excited rotational state to those in the ground state @ 25 C. Assume an equilibrium bond distance of 1.275 angstroms. the angstrom part of the problem throws me off, I usually start these out by solving Change in E = ( h ) ( c )(Wo), but this is a q (rot) prob, not a q (el

Conversions

The volume of a certain bacterial cell is 1.60 µm3. (a) What is its volume in cubic millimeters (mm3)? (b) What is the volume of 105 cells in liters (L)? [show all the conversion factors that were used in calculating the answers]

Particle in a Box

A particle is constrained to lie along a one-dimensional line segment between 0 and a. The probability of finding the particle along this line segment is seen in attached file. A. Find the proportionality constant, ie., normalize the function. B. Calculate the expectation values of X and X^2 for n=1 and n=2. C. Find t

Dilution Processes

I need help in solving this word problem: A corrupt barman attempts to prepare 100ml of some drink by mixing 30ml of ethanol with 70 ml of water. Does he succeed? If not, what volumes should have been mixed in order to arrive at a mixture of the same strength but of the required volume?

Precipitation calculations

Precipitation Calculations. Will a precipitate of calcium sulfate (Ksp = 2.4 x 10-5) form when 50.0 mL of 0.00150 M calcium chloride and 25.0 mL of 0.0100 M sodium sulfate are mixed? Why or why not?

Colors and bands

What color has the smallest band in the spectrum of a tungsten light bulb? I have guessed yellow because the waves are shortest but don't know if I am right.