Perform the following mathematical operation, and
report the answer to the
appropriate number of
significant figures.

140.3 - 120.124 = [?]

Apeak with a retention time of 407 s has a width at half-height (w1/2) of 7.6 s. a neighboring peak is eluted 17 s later with a w1/2 of 9.4 s. a compound that is known not to be retained was eluted in 2.5 s. the peaks are not baseline resolved. how many theoretical plates would be needed to achieve a resolution of 1.5?

Astudent reacts 13 moles of iron with 21 moles of oxygen according to the following equation:

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