Suppose now that you wanted to determine the density of a small crystal to confirm that it is silicon. from the literature, you know that silicon has a density of 2.33 g/cm3 . how would you prepare 20.0 ml of the liquid mixture having that density from pure samples of chcl3 (d = 1.492 g/ml) and chbr3 (d = 2.890 g/ml)? (note: 1 ml = 1 cm3 .)

An empty fuel tank can still contain and therefore can be even more dangerous than one full of liquid fuel.

8.98 dm3 of hydrogen gas is collected at 38.8 °c. find the volume the gas will occupy at -39.9 °c if the pressure remains constant.

15. which of the following is not human-caused groundwater pollution? a. water in an aquifer dissolves elements such as arsenic and mercury from surrounding rock. b. water in an aquifer is contaminated by leachate that seeps into the ground from a landfill. c. water in an aquifer becomes polluted with chemicals used in hydraulic fracturing, or fracking. d. water in an aquifer absorbs harmful bacteria from the drainage field of a septic tank.