Question

DATA ANALYSIS 3. Some salts, when they form, may trap water are referred to as hydrated salts. The structure. This is referred to as an anhydrous sait. of water molecules per unit of salt (e.g. xg H, per When heated, the water can be drivent from the salt it results in the anhydrous form of that sa chloride. In its anhydrous form the formula for form the formula for cobalt chloride is CoCl2 XH2O per given unit of salt. If a sample of hydrated cobalto was removed, calculate the value of x from the following data. , may trap water molecules within their structure. These ed salts. The same salt can form with no water trapped in its anhydrous salt. Hydrated salts have a specific ratio e.g. xg H,O per 1g salt or xmol H2O per 1mol salt). ater can be driven from the salt and when all of the water is removed arous form the formula for chal chloride is Coci.. In its hydrated us form of that salt. One example is the salt cobalt onde is COCI, . xH, where x equals the number of waters Ta sample of hydrated cobalt chloride was heated until all water Molecular mass Coci, (anhydrous) - 129.84 Molecular mass H,O- 18.02 Mass CoCl, before heating - 19.81g Mass CoCl, after heating (to constant mass) - 15.52g SY

Answer 1

10.131 18.029 1 mol mol = 4:29. Number of moles of water (H2O) = (19.81g-15.529)/18.02 gir 4.29g 18.02 g/mol = 0.23807 mol. Number of moles of Call, Canhyd.) selt= 15 sag - 0.119532 mol. 129.84 g/mol Colheado o Collt a ho ratio of moles of the moles of Colla a 0.23807 - = 1.992 50.119532 2. The value of n=2 and salt is Coll. 2H2O atom economy of the reaction = molar mass of product x 100 4. molarmers of all reactants 129.84 - x 100 = 78.274. (129.84+2X18.02) = 78.3 %