2×21=how many are there

Ibeg i need 20. a reaction produces 4.93 l of oxygen, but was supposed to produce 1 mol of oxygen. what is the percent yield?

The excretory system,need answers for all: )

Effect of rotenone and antimycin a on electron transfer rotenone, a toxic natural product from plants, strongly inhibits nadh dehydrogenase of insect and fish mitochondria. antimycin a, a toxic antibiotic, strongly inhibits the oxidation of ubiquinol. (a) explain why rotenone ingestion is lethal to some insect and fish species. (b) explain why antimycin a is a poison. (c) given that rotenone and antimycin a are equally effective in blocking their respective sites in the electron-transfer chain, which would be a more potent poison? explain.