A1.75-cm diameter naphthalene mothball is suspended in an air stream at 280 k, 1.0 atm, and constant velocity of 1.4 m/s. solid naphthalene exerts a vapor pressure of 2.8 pa at 280 k. consequently, the naphthalene very slowly sublimes into the passing air stream, with the rate limited by convective mass transfer. the density of solid naphthalene is 1.14 g/cm3, and the molecular weight is 128 g/mole. a. what is the initial evaporation rate of naphthalene mothball? b. how long will it take for the mothball to shrink to half of its original diameter? remember: as the mothball shrinks, its diameter is decreasing, which in turn affects the reynolds and sherwood numbers.

If a gas has an initial pressure of 101kpa and a volume of 10l, then it expands to a volume of 20l, what is the new pressure?

Which property of water causes water drops to bead on a freshly waxed car?

Air pressure is measured in pascals. for a professional american football game, the ball should be inflated to about 90,000 pascals. scientists studied the effects of air temperature on the pressure inside american footballs by taking these steps: 1. prepare 100 footballs. 2. measure each football's air pressure. 3. divide footballs into 10 groups. 4. place the groups in different lockers cooled to different air temperatures. 5. after 12 hours, remove the footballs from lockers. 6. measure each football's pressure again. 7. compare the new pressures to the starting pressures. what two terms best describe the variable "air pressure inside the football" in this experiment? independent, qualitative independent, quantitative dependent, qualitative dependent, quantitative