At 213.1 k a substance has a vapor pressure of 45.77 mmhg. at 243.7 k it has a vapor pressure of 193.1 mm hg. calculate its heat of vaporization in kj/mol.

Which form of cell division creates the sperm and egg, resulting in half of the chromosomes as the other cells?

Which of the following are forms of phase changes a. freezing b. condensation c. heating d. exchanging

Aspring has a relaxed length of 33 cm (0.33 m) and its spring stiffness is 6 n/m. you glue a 76 gram block (0.076 kg) to the top of the spring, and push the block down, compressing the spring so its total length is 15 cm. you make sure the block is at rest, then at time t=0 you quickly move your hand away. the block begins to move upward, because the upward force on the block by the spring is greater than the downward force on the block by the earth. calculate y vs. time for the block during a 0.09-second interval after you release the block, by applying the momentum principle in three steps each of 0.03-second duration.