For substance a, the entropy of the solid at 98.36 k is 7.36 cal/molk, at this temperature it takes place the transition from one solid form to another, the transition heat is 284.3 cal/mol. the increase in entropy of the second solid modification is 98.36 k to 158.91 k and is 5.05 cal/molk; the temperature of 158.91 k is the melting temperature of the solid. the melting heat of the solid is 476 cal/mol. from the melting point to the boiling point, 188.07 k, the increase of entropy is 2.36 cal/molk and the heat of vaporization is 3860 cal/mol. a heat capacity from the boiling point to 298 k is 6.98 cal/molk to an atmosphere of pressure. to calculate the absolute entropy of a considering as ideal gas an atmosphere and 298 k.

The temperature at a point (x, y) is t(x, y), measured in degrees celsius. a bug crawls so that its position after t seconds is given by x = 6 + t , y = 8 + 1 3 t, where x and y are measured in centimeters. the temperature function satisfies tx(3, 9) = 5 and ty(3, 9) = 4. how fast is the temperature rising on the bug's path after 3 seconds? (round your answer to two decimal places.)

Glass has a hardness that is in the middle of the hardness scale. what is the hardness of glass?

In the future, people will only enjoy one sport: electrodisc. in this sport, you gain points when you cause metallic discs hovering on a field to exchange charge. you are an electrodisc player playing the popular four disc variant. the disks have charges of qa = −8.0 µc, qb = −2.0 µc, qc = +5.0 µc, and qd = +12.0 µc. (1) you bring two disks together and then separate them. you measure the resulting charge of these two disks and find that it is +5.0 µc per disk. which two disks did you bring together? (a) a and b (b) a and c (c)a and d (d)b and c(e) b and d (f) c and d. (2) you bring three disks together and then separate them. you measure the resulting charge of these three disks and find that it is +3.0 µc per disk. which three disks did you bring together? a, b, and c (a) a, b, and d (c) a, c, and d (d) b, c, and d. (3) given the resulting charge of each disk measured in (b) is +3.0 µc, how many electrons would you need to add to a disk of this charge to electrically neutralize it? electrons