Calculate the average atomic mass of a sample of a mixture of argon (Ar). The mixture is 90% argon-36 and 10% argon-38. Argon-36 has an atomic mass of 35.968 amu. Argon-38 has an atomic mass of 37.962 amu

What semimetal can form four single covalent bonds.

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.

Stage in which a star’s outer layers have started to cool and grow outward?