Asound wave has a frequency of 615 hz in air and a wavelength of 0.54 m. what is the temperature of the air? assume the velocity of sound at 0◦c is 335 m/s. answer in units of ◦c.

Hydrogen and helium are both members of?

Asheet of steel 1.5 mm thick has nitrogen atmospheres on both sides at 1200oc and is permitted to achieve a steady-state diffusion condition. the diffusion coefficient for nitrogen in steel at this temperature is 6 x 10- 11 m2 /s, and the diffusion flux is found to be 1.2 x 10-7 kg/m2 -s. also, it is known that the concentration of nitrogen in the steel at the high-pressure surface is 4 kg/m3 . how far into the sheet from this high-pressure side will the concentration be 2.0 kg/m3 ? assume a linear concentration profile.

Which compound is held together by the electrostatic force between two ions? a. co2 b. cci4 c. h2s d. mgf2