What is the hybridization of phosphorus in phosphonium ion?

In numbering carbon atoms in the parent chain of a hydrocarbon, why would you number from right to left, rather than left to right

If a 12-v battery is connected to a circuit that has a current of 3.0 a, what is the total resistance in the circuit? 36 ohms 4 ohms 0.25 ohms

Which statement is usually true about the relationship between activation energy and reaction rates? low activation energy barriers result in low rates. high activation energy barriers result in low rates. low activation energy barriers result in no reaction. high activation energy barriers result in no reaction.