Determine the energy of the electron in the 1s orbital of a helium ion (he+ ).

Calculate the number of molecules present in 0.750 mol of mgo.

Which statement is true about a catalyst? a: a catalyst decreases the rate of the reaction. b. a catalyst is consumed during a chemical reaction. c. a catalyst lowers the activation energy of a reaction. d. a catalyst increases the reactant concentration during a reaction.

How many moles of bromine are needed to produce 3.23 moles of potassium bromide