Dinitrogen monoxide gas is collected at in an evacuated flask with a measured volume of . When all the gas has been collected, the pressure in the flask is measured to be . Calculate the mass and number of moles of dinitrogen monoxide gas that were collected. Round your answer to significant digits.

Solar energy is energy from the sun that is converted into thermal or energy. a. nuclear b. mechanical c. electrical d. chemical

Compared with the freezing-point depression of a 0.01 m c6h12o6 solution, the freezing-point depression of a 0.01 m nacl solution is

Two nitro no2 groups are chemically bonded to a patch of surface. they can't move to another location on the surface, but they can rotate (see sketch at right). it turns out that the amount of rotational kinetic energy each no2 group can have is required to be a multiple of ε, where =ε×1.010−24 j. in other words, each no2 group could have ε of rotational kinetic energy, or 2ε, or 3ε, and so forth — but it cannot have just any old amount of rotational kinetic energy. suppose the total rotational kinetic energy in this system is initially known to be 32ε. then, some heat is removed from the system, and the total rotational kinetic energy falls to 18ε. calculate the change in entropy. round your answer to 3 significant digits, and be sure it has the correct unit symbol.