The human lungs can T function satisfactorily up to a limit where the pressure differ- ence between the outside and inside of the lungs is one-twentieth of an atmosphere. If a diver uses a snorkel for breathing, how far below the water can she swim? Assume the diver is in salt water whose density is 1025 kg/m³. 25.

The repulsive force between Na+ and Cl- ions can be written as F = Be-T/R where B = 5.45 x 10-6 N and R = 0.321 Å. At equilibrium, this force is equal to the magnitude of the attractive force given by F Determine the value of r at equilibrium. e² 4π€or²

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A sample of copper has a mass of 10.68 g when measured in air. It has a mass of 9.47 g when measured in water.    Answer these four questions: What is the density of the sample? How many atoms are in the sample?  What is the simple volume of the space including and surrounding each atom? Assume the atoms are evenly distributed throughout the sample. That is no FCC, BCC, or HCP crystal structure.  What is the diameter of each atom?

Pls help ASAP. Pls show all work annd circle the final answer.

Question 3 A A plastic bowl is floating in a sink full of water. Which of the following describes the microscopic cause of the buoyant force exerted on the bowl by the water? Gravitational attraction between the molecules of the bowl and the molecules of the water Electrostatic attraction between the nuclei in the molecules in the bowl and the electrons in the molecules of the water Electrostatic repulsion between the nuclei in the molecules in the bowl and the nuclei in the molecules of the water Electrostatic repulsion between the electrons in the molecules in the bowl and the electrons in the molecules of the water