An isothermal plug flow reactor is used to remove an environmental contaminant from polluted water via a 2nd-order reaction. a residence time of 7.5 min in the reactor results in 90% conversion. to obtain 99% conversion, what is the closest time below that would be expected? explain your answer. a. 8.2 min b. 15 min c. 80 min d. 250 min e. 1500 min

The earth's moon is unusually large. two popular theories of the moon's origin include the "sister world" hypothesis, which states that the moon formed from the same materials as the earth, near enough to the earth that they fell into orbit around each other. a second theory is the "capture" hypothesis, in which the moon formed elsewhere in the solar system, and the earth's gravity pulled it into its orbit. studies of what the moon is made of indicate that some of its materials had to come from the earth or from the same area of the solar system where the earth had formed. at the same time, the moon does not contain much of the material that makes up the earth's core, so the moon could not have formed from the same materials as the earth. how do the two facts above affect the described theories of the moon's origin? a. they show that scientists will never agree on where the moon came from. b. they show that more experiments on moon formation need to be done. c. they show that no theory accounts for the existence of the moon. d. they show that neither theory is complete and entirely correct.

Astudent is asked to identify and element that is pale yellow brittle solid and does not conduct electricity. at which location in this periodic table would the element most likely be found?

Identify the lewis base in this balanced equation: fe3+ h2o fe(h2o)63+