10H 2O) was heated to remove the water.Therefore:ģ) We want to know how many moles of H 2O are present for every one mole of (NH 4) 3PO 4: Problem #6: Determine the formula and name for the hydrate: 73.42% ammonium phosphate and 26.58% water.ġ) Assume 100 grams of the compound is present. The ratio we want in smallest whole-numbers is this -> 0.24025 mol to 2.55545 mol What is the water of hydration for this hydrate of sodium carbonate? The concentration of the solution was found to be 0.04805 M. Problem #5b: A solution was made by dissolving 71.50 g of hydrated sodium carbonate in water and making it up to 5.00 L of solution. (105.988 is molar mass of anhydrous sodium carbonate)Ĥ) Moles of water in one mole of hydrate: Determine the formula of hydrated sodium carbonate.ġ) Moles of hydrated sodium carbonate in 5.00 liters:Ģ) Molecular weight of hydrated sodium carbonate: The concentration of the solution was determined to be 0.0366 M. Problem #5a: A solution was made by dissolving 52.0 g of hydrated sodium carbonate in water and making it up to 5.00 dm 3 of solution. The standards for being in agreement might vary from one instructor to the next, so make sure to consult with your lab teacher on this point. In some cases, where an extra amount of care must be taken, you would want three straight weighings that were in agreement.Īlso, weighs being in agreement does not mean that they are exactly the same. If the two weights disagree, you continue heating and weighing until you gets weights that agree. If the two weights are in agreement, then you are done heating. H 2O -> 0.43 g / 18.015 g/mol = 0.0239 molĬoCl 2 -> 0.01194 mol / 0.01194 mol = 1ĥ) How can you make sure that all of the water of hydration has been removed?Īfter weighing the anhydrous CoCl 2, you would continue to heat it. What is the formula for the original hydrate? How can you make sure that all of the water of hydration has been removed?Ģ) Determine moles of anhydrous CoCl 2 and H 2O:ĬoCl 2 -> 1.55 g / 129.839 g/mol = 0.01194 mol When cooled, the mass of the remaining dehydrated compound is found to be 1.55 g. Problem #4: A 1.98 g sample of a cobalt(II) chloride hydrate is heated over a burner. What is the value of n in the hydrate's formula?ġ) Calculate moles of anhydrous barium chloride: After heating, 4.26 g of anhydrous barium chloride, BaCl 2, remains.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |