Download Equatioon Stiochiometry 1.notebook and more Exams Stoichiometry in PDF only on Docsity! Equatioon Stiochiometry 1.notebook 1 November 19, 2013 Nov 175:33 PM 1. When potassium chlorate is heated, it decomposes to potassium chloride and oxygen gas. a) Write a balanced molecular equation showing this reaction. Include phases. 2KClO3(s) à 2KCl(s) + 3O2(g) b) If 0.500 grams of potassium chlorate is decomposed, calculate the moles of potassium chloride and moles of oxygen gas that will be produced. 0.500 g KClO3 x (1 mol KClO3/122.6 g KClO3) x (2 mol KCl/2 mol KClO3) = 0.00408 mol KCl 0.500 g KClO3 x (1 mol KClO3/122.6 g KClO3) x (3 mol O2/2 mol KClO3) = 0.00612 mol O2 Nov 175:33 PM c) Calculate the masses of potassium chloride and oxygen gas that will be produced. 0.00408 mol KCl x (74.6 g KCl/1 mol KCl) = 0.304 g KCl 0.00612 mol O2 x (32.0 g O2/1 mol O2) = 0.196 g O2 Or 0.500 = 0.304 + X, x = 0.196 g O2 Equatioon Stiochiometry 1.notebook 2 November 19, 2013 Nov 175:34 PM 2. A 4.25 mole sample of molten aluminum chloride undergoes electrolysis. a) write a balanced molecular equation showing this reaction 2AlCl3(l) à 2Al(s) + 3Cl2(g) b) calculate the masses of products formed. 4.25 mol AlCl3 x (2 mol Al/2 mol AlCl3) x (27.0 g Al/1 mol Al) = 115 g Al 4.25 mol AlCl3 x (3 mol Cl2/2 mol AlCl3) x (71.0 g Cl2/1 mol Cl2) = 453 g Cl2 Nov 175:35 PM 3. A sample of magnesium metal reacts pure nitrogen gas. a) write a balanced molecular equation for this reaction 3Mg(s) + N2(g) à Mg3N2(s) b) calculate the masses of each of the reactants that would be needed to produce exactly 0.400 mole of magnesium nitride. 0.400 mol Mg3N2 x (3 mol Mg/1 mol Mg3N2) x (24.3 g Mg/1 mol Mg) = 29.2 g Mg 0.400 mol Mg3N2 x (1 mol N2/1 mol Mg3N2) X (28.0 g N2/1 mol N2) = 11.2 g N2
