Prior info Flask mass = 31.601 g Water + flask mass = 60.735 g Water density = 0.9973 g/cm^3 Mass of water = (water + flask mass) - (flask mass) = 60.735 - 31.601 Mass of water = 29.134g Volume of water = mass of water/density of water = 29.134 g/0.9973 g/cm^3 = 29.2139 cm^3 Volume of flaskLiquid + flask mass = 56.796 g Mass of liquid = (Liquid + flask mass) - (flask mass) = 56.796 - 31.601 = 25.195 g Density of liquid = Mass of liquid/Volume of flask = 25.195 g/29.2139 cm^3 = 0.8624 g/cm^3 Finding the density of a solid. The student then emptied the flask and dried it once again. To the empty flask she added pieces of metal until the flask was about half full. She weighed the stoppered flask and its metal contents and found that the mass was 99.323 g. She then filled the flask with water, stoppered it, and obtained a total mass of 120.827 g for the flask, stopper, metal, and water. Find the density of the metal. a. To find the density of the metal we need to know its mass and volume. We can easily obtain is mass by the method of differences:

(Mass of metal) = g - g = g b. To determine the volume of metal, we note that the volume of the flask must equal the volume of the metal plus the volume of water in the filled flask containing both metal and water. If we can find the volume of water, we can obtain the volume of metal by the method of differences. To obtain the volume of the water we first calculate its mass:

Mass of water = mass of (flask + stopper + metal + water) – mass of (flask + stopper + metal) Mass of water = g - g = g The volume of water is found from its density, as in 1b. Make the calculation. Volume of water = cm3 c. From the volume of the water we calculate the volume of metal:

Volume of metal = volume of flask – volume of water

Volume of metal = cm3 - cm3 =

cm3

From the mass and volume of the metal we find the density, using the equation in 1b. Make the calculation.

Density of metal = g/cm3 Now go back to Question 1 and check to see that you have reported the proper number of significant figures in each of the results you calculated in this assignment. Use the rules on significant figures as given in your chemistry text.

experimental-chemistry