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How much work is done by an ideal gas in expanding isothermally from an initial volume of 3.00 liters at 20.0 atm to a final volume of 24.0 liters?

A solution is prepared by dissolving 35.0 g of hemoglobin (Hb) in enough water to makeup 1 L in volume. If the osmotic pressure of the solution is found to be 10.0 mmHg at 25C.

calculate the molar mass of hemoglobin.

A 7.85-g sample of a compound with the empirical formula C5H4 is dissolved in 301 g of benzene. The freezing point of the solution is 1.05 C below that of pure benzene.

What are the molar mass and molecular formula of this compound?

Ethylene glycol (EG), CH2(OH)CH2(OH), is a common automobile antifreeze. It is water soluble and fairly nonvolatile (b.p. 197 C). Calculate the freezing point of a solution containing 651 g of this substance in 2505 g of water. Would you keep this substance in
your car radiator during the summer? The molar mass of ethylene glycol is 62.01 g.

The density of a 2.45 M aqueous solution of methanol (CH3OH) is 0.976 g/mL. What is the molality of the solution? The molar mass of methanol is 32.04 g.

Estimate the enthalpy change for the combustion of hydrogen gas:

2H2(g) + O2(g) ---> 2H2O(g)

Hence, H2O is a polyatomic molecule, and so we need to use the average bond enthalpy value for the O-H bond.

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Sulfur (S) is a nonmetallic element that is present in coal. When coal is burned, sulfur is converted to sulfur dioxide and eventually to sulfuric acid that gives rise to the acid rain phenomenon. How many atoms are in 16.3 g of S?

Calculate the wavelength of the “particle” in the following two cases:

a) The fastest serve in tennis is about 150 miles per hour, or 68 m/s. Calculate the wavelength associated with a 6.0 x10^-2 kg tennis ball traveling at this speed.

b) Calculate the wavelength associated with an electron 9.1094X10^-31 kg moving at 68 m/s.

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What is the wavelength of a photon (in nanometers) emitted during a transition from the ni =5 state to the nf = 2 state in the hydrogen atom?

The wavelength of the green light from a traffic signal is centered at 522 nm. What is
the frequency of this radiation?

A 466-g sample of water is heated from 8.50 C to 74.60 C. Calculate the amount of
heat absorbed (in kilojoules) by the water.