A chemist prepares a solution of mercury(I) chloride Hg2Cl2 by measuring out
0.000126 μmol of mercury(I) chloride into a 100. mL volumetric flask and filling the flask to the mark with water.
Calculate the concentration in mmol/L of the chemist's mercury(I) chloride solution.
Round the answer to three significant figures.

Can you guys me with question no. 5!

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.

To apply in a gold the individual gold atoms are united to each other by means of a metallic bond. how would you use the gold block to determine the atomic radius of a gold atom?