The lifetime of a star can be estimated in "solar lifetimes" by dividing 1 by the mass of the star, raised to the 2.5 power (t-1/m5 where mass is given in solar masses. what is the expected lifetime of a star that has three times the mass of the sun? 7-[)solar lifetimes

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.

The diagrams to the right show the distribution and arrangement of gas particles in two different containers. according to kinetic-molecular theory, which of the following statements is true? check all that apply. if the temperatures of both containers are equal, container a has greater pressure than container b. if the volume of container a decreased, its pressure would decrease. if the pressure in both containers is equal, container a has a lower temperature than container b.

Ok, so i have 2 questions. try to answer them both: (the topic is fire) 1) how can you represent the chemical reaction of fire? 2) what kind of bond is formed in this chemical reaction