Which of the following enzymes serve as catalysts in metabolism? i. amylase ii. lactase iii. pepsin iv. polymerase

What is the number of moles of chemical units represented by 9.03x10^24? and how do i show work? (dumb it down )

What can be found in the ionosphere

Hydrogenation reactions, in which h2 and an "unsaturated" organic compound combine, are used in the food, fuel, and polymer industries. in the simplest case, ethene (c2h4) and h2 form ethane (c2h6). if 140 kj is given off per mole of c2h4 reacting, how much heat (in mj) is released when 12 kg of c2h6 forms?