PLEASE HELP ASAP In the reaction 2H2 + O2 → __H2O, what coefficient should be placed in front of H2O to balance the reaction?

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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.

Drug abuse will not lead to physical and psychological dependence. true or false ?

What was bohr’s contribution to the planetary model