Calculate the mass of the air contained in a room that measures 2.50 m × 5.50 m × 3.00 m (density of air = 1.29 g/dm3 at 25°C).

Apure solvent has a vapor pressure the vapor pressure of a solution. a. equal to b. lower than c. higher than

Which of the following is an indication that a substance has undergone a chemical change? a. no new product has been formed. b. the color of the substance has not changed. c. the original constitute has not changed. d. the molecular structure has changed.

What relationship exists between an enzyme and a catalyst?