Scuba divers breathing air at increased pressure can suffer from nitrogen narcosis-a condition resembling drunkenn esswhen the partial pressure of nitro gen exceeds about 4 atm. What property of gas/water solutions causes this to happen? How can a diver reverse this effect?

An aq ueo us NaCl so lution is made usin g 112 g of NaCl diluted to a total soluti on volume of 1.00 L. Calculate the molarity, rnolality, and mass percent of the solution. (Assume a density of 1.08 g/ mL for the solution .)

Calculate the mass of nitrogen dissolved at room temperature in an 80.0-L home aquarium. Assume a total pressure of 1.0 atm and a mole fraction for nitrogen of 0.78.

A person preparing a fish tank fills the tank with water that has been boiled (and then cooled). When the person puts fish into the tank, they die. Explain .

Scuba divers breathing air at increased pressure can suffer from oxygen toxicity-too much oxygen in the bloodstream-when the partial pressure of oxygen exceeds about $1.4 \mathrm{~atm}$. What happens to the amount of oxygen in a diver's bloodstream when he or she breathes oxygen at elevated pressures? How can this be reversed?

Lithium iodide has a lattice energy of $-7.3 \times 10^{2}$ kJ/mol and a heat of hydration of - 793 kJ/mol. Find the heat of solution for lithium iodide and determine how much heat is evolved or absorbed when 15.0 g of lithium iodide completely dissolves in water.

The air a scuba diver breathes is pressurized to counteract the pressure exerted by the water surrounding the diver’s body. Breathing the high-pressure air causes excessive amounts of nitrogen to dissolve in body fluids, especially the blood. If a diver ascends to the surface too rapidly, the nitrogen bubbles out of the body fluids (much as carbon dioxide bubbles out of a soda immediately after the container is opened). This results in a painful and potentially lethal medical condition known as the bends. Why does breathing a mixture of helium and oxygen rather than air help divers avoid getting the bends?

An aqueous solution containing 35.9 g of an unknown molecular (no nelectrolyte) compound in 150.0 g of water has a freezing point of - 1.3$^{\circ} \mathrm{C}$. Calculate the molar mass of the unknown compound.

Choose the word or words that best complete the sentence. Tropical grassland with scattered trees is called______ A. savanna B. prairie C. steppe D. tundra

The solubility of carbon tetrachloride $(CCl_4)$ in water at 25$^{\circ} \mathrm{C}$ is 1.2 g/L. The solubility of chloroform ($CHCl_3$) at the same temperature is 10.1 g/L. Why is chloroform almost ten times more soluble in water than carbon tetrachloride?

Simplify

$$\left[\begin{array}{rr}{6} & {-1} \\ {3} & {2}\end{array}\right]\left[\begin{array}{rr}{5} & {2} \\ {-8} & {4}\end{array}\right]$$

Potassium nitrate has a lattice energy of - 163.8 kcal/ mol and a heat of hydration of - 155.5 kcal/ mol. How much potassium nitrate has to dissolve in water to absorb $1.00 \times 10^{2}$ kJ of heat?

Use the document to answer the following questions. At the United Nations Millennium Summit in 2000, world leaders agreed to work together to achieve eight development goals by 2015. These goals included eradicating extreme poverty and hunger, achieving universal primary education, promoting gender equality reducing child mortality, and combating diseases. We will have time to reach the Millennium Development Goals... but only If we break with business as usual. Success will require sustained action it takes time to tram the teachers, nurses and engineers; to build the roads, schools and hospitals; to grow the small and large businesses able to create the jobs and income needed. So we must start now. And we must more than double global development assistance over the next few years. Nothing less will help to achieve the Goals.” —Kofi Annan, former UN Secretary-General. June 7, 2005. What do these goals tell you about the economies of many countries?

Pick an appropriate solvent to dissolve magnesium bromide (ionic).