If the pH of a NaOH solution is 11.7, what is the concentration of the NaOH solution ? b) calculate the number of moles of NaOH needed to make 2 Liters of solution.

Maria wants to determine which type of disinfectant kills the most bacteria. which of the following is the best way for maria to determine this? a. ask ten different companies that make disinfectants which type is best. b. put the same amount and species of bacteria on ten identical plates, and add ten different kinds of disinfectant to each plate. c. interview ten different people to determine which type of disinfectant they prefer. d. put the same amount and species of bacteria on ten identical plates, and add a different disinfectant to each plate.

Electric charge is what ? a. kinetic energy b. radiation c. discovery d. electricity

What is the independent variable in this investigation? mass volume sample number substance density