Technetium-99 is used for brain scans. The isotope has a half-life of six hours. A laboratory needs 200 g for an experiment. If shipment takes 72 hours, how much Technetium-99 should be prepared so that the appropriate amount remains after shipping?

If 90.0 grams of ethane reacted with excess chlorine, how many grams of dicarbon hexachloride would form

Imagine that twenty i. u.’s of enzyme z were catalyzing the above reaction for one minute, under vmaxconditions, in a 3.00 ml assay volume. the assay is buffered with 20 mm phosphate buffer, ph 7.60. what will the ph be at the end of that one minute?

What is the subscript for oxygen in its molecular formula