Download Percent Composition of a Hydrate and more Slides Chemistry in PDF only on Docsity! Percent Composition of Hydrates 2020.notebook 1 March 05, 2020 Jan 172:34 PM Percent Composition of a Hydrate Aim: What is a hydrate? How do we analyze the composition of a hydrate? Jan 172:34 PM What is a hydrate? Hydrate A salt compound that contains water molecules within it's crystal structure. Hydrate formulas: CuSO4●5 H2O 1 CuSO4 has 5 H2O molecules attached. GFM of CuSO4 ● 5 H2O Percent Composition of Hydrates 2020.notebook 2 March 05, 2020 Jan 172:34 PM What is a hydrate? Hydrate A salt compound that contains water molecules within it's structure. Hydrate formulas: CuSO4●5 H2O 1 CuSO4 molecule w/ 5 H2O molecules attached. Hydrate symbol. The "dot" represents water molecules attached. GFM of CuSO4 ● 5 H2O Jan 172:34 PM Heating a Hydrate • When a hydrate is heated, the water molecules evaporate. • The hydrate is now called an anhydrate or andhydrous salt it no longer contains water. • mass of water= mass of hydrate mass of anhydrous salt Percent Composition of Hydrates 2020.notebook 5 March 05, 2020 Jan 172:34 PM Percent of water in a Hydrate using GFM 4. What is the percent composition of water in the hydrate, Ba(ClO3)2 ● 7 H2O? 3. What is the percent composition of water in the hydrate, MnCl7 ● 4H2O? (Theoretical % of H2O in a Hydrate) Jan 172:34 PM PRACTICE HYDRATE PROBLEMS 3. What is the percent composition of water in the hydrate, MnCl7 ● 4H2O ? 4. What is the percent composition of water in the hydrate, Ba(ClO3)2 ● 7 H2O ? GFM MnCl7● 4 H2O Mn: 54.9 H: 8.0 Cl: 248.5 O: 64.0 375. 4 g/mol GFM Ba(ClO3)2 ● 7 H2O Ba: 137.3 H: 14.0 Cl: 71.0 O: 112.0 O: 96.0 430.3 g/mol % H2O = 72.0 x 100 = 19.2 % 375.4 % H2O =126.0 x 100 = 29.3 % 430.3 Percent Composition of Hydrates 2020.notebook 6 March 05, 2020 Jan 172:34 PM Water in a Hydrate (Experimental % of H2O) 1. The initial weight of a hydrate is 5.06 grams. After heating, the final weight of the anhydrate is 4.50 grams. Determine the percent composition of water in the hydrate. Water in a Hydrate by Formula Analysis What is the percent by mass of water in FeCl3●6 H2O? % H2O = mass H2O x 100 mass hydrate % H2O = 0.56 g x 100 = 11.1% 5.06 g mass hydrate= 5.06 g mass anhydrate= 4.50 g mass water= 5.064.50 = 0.56 g GFM FeCl3●6 H2O Fe: 1 x 55.8= 55.8 H: 12 x 1.0= 12.0 Cl: 3 x 35.5= 106.5 O: 6 x 16.0 = 96.0 162.3 g + 108.0 g = 270.3 g salt component water component hydrate mass % H2O = mass H2O x 100 mass hydrate % H2O = 108.0 g x 100 270.3 g % H2O = 39.95 % mass mass