The first supersonic flight was in 1947. It was just above the speed of sound. Which altitude would a student expect Captain Yeager to have used for his flight?

Write the symbol for every chemical element that has atomic number greater than 3 and atomic mass less than 12.0 u.

Which of the following statements is true? a. elements in the last period are radioactive. b. atomic weight is the same as atomic mass. c. elements in the same group have the same number of electron shells. d. atomic number equals the number of neutrons in the nucleus of an atom.

Under what conditions will a gas be most likely to exhibit the ideal gas properties predicted by the ideal gas law? 1)high pressures and high temperature, because particles are forced closer together with higher kinetic energy, so intermolecular forces of attraction are weaker 2)high pressure and low temperature, because particles are forced closer together and moving slower, so the volume of the particles is less significant 3) low pressure and high temperature, because particles are spread farther apart and moving faster, so the intermolecular forces of attraction are weaker 4)low pressure and low temperature, because particles are spread farther apart with lower kinetic energy, so the volume of the particles is less significant