30 according to newton's second law of motion, if a rigid body of unchanging mass is observed accelerating, what must be happening?

a. a force is being applied to the mass

b. the mass must be changing

c. no force was or is being applied to the mass

d. a force was once applied but is now not being applied.

Elements in group 2 are all called alkaline earth metals. what is most similar about the alkaline earth metals?

Achemist at a pharmaceutical company is measuring equilibrium constants for reactions in which drug candidate molecules bind to a protein involved in cancer. the drug molecules bind the protein in a 1: 1 ratio to form a drug-protein complex. the protein concentration in aqueous solution at 25 ˚c is 1.74 x10-6 m . drug a is introduced into the protein solution at an initial concentration of 2.00 x10-6m. drug b is introduced into a separate, identical protein solution at an initial concentration of 2.00 x10-6m. at equilibrium, the drug a-protein solution has an a-protein complex concentration of 1.00 x10-6m, and the drug b solution has a b-protein complex concentration of 1.40 x10-6m.a. calculate the kc value for the a-protein binding reaction.b. calculate the kc value for the b-protein binding reaction.c. assuming that the drug that binds more strongly will be more effective, which drug is the better choice for further research?

You have 125 g of a certain seasoning and are told that it contains 70.0 g of salt. what is the peroentage of salt by mass in this seasoning?