Mean temperature difference in an exchanger. a 1-2 exchanger with one shell pass and two tube passes is used to heat a cold fluid from 37.8 c to 121.1 c by using a hot fluid entering at 315.6°c and leaving at 148.9℃ calculate the δτǐn and the mean temperature difference δ7, in k. δ7," = 148.9 k.37,-131.8 k

substituting a hydrogen atom with a halogen in a hydrocarbon:

- the single bond remains single. a is wrong.

- the bond with hydrogen is as strong as with a halogen. c is wrong

- a hydrocarbon is saturated if there is no double bond. we do not know that so d is wrong.

- carbon will always have four valence electrons. e is wrong.

by elimination, the correct answer is b. the boiling point of the new compound increases.

answer; the numbers of valence electrons in the acetic acid molecule (ch3co2h) is 24;