Question

DATE NAME SECTION POSTLABORATORY ASSIGNMENT 1. Predict the empirical formula for each of the following compounds given the formula of magnesium oxide, MgO. (a) calcium oxide (b) strontium oxide (c) barium oxide (d) radium oxide 2. Predict the empirical formula for each of the following compounds given the formula of sodium chloride, NaCl. (a) sodium fluoride (b) potassium chloride (c) lithium bromide (d) rubidium iodide 3. A 1.250 g sample of copper wire was heated in air and reacted with oxygen to give 1.565 g of copper oxide product. Calculate the empirical formula of the copper oxide. LLLLLLCCCCCCCCOOOOOOOOOODDDDDDDDDDDDDD 4. A 1.167-g sample of iron powder reacted with 0.680 g of sulfur powder to give iron sulfide product. Calculate the empirical formula of the iron sulfide. Empirical Formulas of Compounds

Answer 1

Emperical formbe of followiny ! Cao sro a> Callium oxide b) & frontium oxide c) barium oxide → de radium oxide - Bao Rao Emperical formle of following :- a> Sodium flouride NOF b) potassium chloride kal e lithium bromide Libr de Rubidium Iodide Rb I mass of au = 1.250 - mole of custom co = 0.0197 moles Similarly 0 = o 1.565- 1.250 0.3159 mars of ... moles of 0 = 0.315= 0.0197 mods Now molan Radio of cu: o cuio E) 0.0197 : 0.0197 1:1 I un Imperical formate = Cuo 16

given mass of fe = 1. 167g. mole of fe = 1. 1679 - 55.8 g/mol = 0.0212 moles or = given man of S= 0.680 g. moles or s = 0.680g = 0.0212 mole of moles of s = 32.8 g/mol &o molon Ratio of fe is = 0.0212 : 0.0212 LESfeis = 1:1 So Empenital formulare = are fes