Summary of chemistry lab report
The two factors which affect the yield of products in a chemical reaction is the amount of starting materials (reactants) and the percent yield of the reaction. Many experimental conditions for example temperature, and pressure can be adjusted to increase yield of the desired product, in chemical reaction, but because chemicals react according to fixed mole ratios( stoichometrically), the only limited amount of product can form from given amount of starting materials. Limiting reactant in our case is the reactant which determines the amount of product generated in a chemical reaction. The objective of the experiment is to determine the limiting reactant in a salt mixture, and to determine the percentage composition of each substance in a salt mixture To better understand the concepts, we look at the reaction below. The reaction of sodium carbonate and calcium chloride is an aqueous system. The molecular form of the equation is Na2CO3.H2O + CaCl2.2H2O → CaCO3 + 2NaCl + 3H2O
As the two reactant salts and sodium chloride are soluble in water but calcium carbonate is insoluble, the ionic equation for the reaction is that we present only the ions that react (after removing the spectator ions)we have the net equation as below CO32- (aq) + Ca2+(aq) CaCO3(s)
From the balanced net ionic equation, 1 mole of carbonate ion from the 1 mole of Na2CO3.H2O(molar mass 124.00 g/mol)reacts with 1 mol of calcium ion from one mol of CaCl2.2H2O( molar mass -147.01g/mol). If the reaction proceeds to completion, the equation also predicts the formation of 1 mol of CaCO3 (molar mass=100.09g/mol) In this experiment, the salt NA2CO3.H2O and CaCl2.2H2O forms the heterogeneous mixture of unknown composition. The mixture is added to water and insoluble CaCO3 forms. The mass of initial salt mixture and the CaCO3 precipitated measured. The percentage composition of the salt...
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