A. 0.8 g/mL, B. 0.800 g/mL, C. 1.25 g/mL, D. 1.3 g/mL QUESTION: What is the density of a liquid if a 25.0 mL sample of the liquid has a mass of 20.00 g? A. 0.8 g/mL, B. 0.800 g/mL, C. 1.25 g/mL, D. 1.3 g/mL Density is defined as the ratio of mass to volume: Density = mass / volume = (20.00 g) / (25.0 mL) = 0.8 g/mL  0.800 g/mL What is the density of a liquid if a 25.0 mL sample of the liquid has a mass of 20.00 g? A. 0.8 g/mL, B. 0.800 g/mL, C. 1.25 g/mL, D. 1.3 g/mL PAUSE CLICK Density is defined as the ratio of mass to volume. Therefore, to calculate density, we simply divide the mass HIGHLIGHT in yellow “mass” by the volume HIGHLIGHT in green “volume” The question gives us 20.00 g HIGHLIGHT in yellow “20.00 g” divided by 25.0 mL HIGHLIGHT In green “25.0 mL” which is equal to 0.8 grams per milliliter. THere are 4 significant digits in 20.00 grams, and 3 significant digits in 25.0 mL CALLOUT The less precise term, 25.0 mL has only 3 significant digits. Therefore, we express our answer to 3 significant digits. We must write as 0.800 grams per mL THe correct answer is B. CLICK PAUSE END RECORDING

Video ID: 1A-8-1 © 2008, Project VALUE (Video Assessment Library for Undergraduate Education), Department of Physical Sciences Nicholls State University Author: Glenn V. Lo Narrator: Funded by Louisiana Board of Regents Contract No. LA-DL-SELECT-13-07/08