1. Precipitation reactions and calculating % Yield To carry out and record results for a precipitation reaction To calculate the % Yield

2. Making barium sulphate & calculating the expected yield During a precipitation reaction two soluble salts are reacted together and one soluble one insoluble product is made. Barium Nitrate + Sodium sulphate  Barium Sulphate + Sodium Nitrate Ba(NO 3 ) 2 + Na 2 SO 4  BaSO 4 + 2NaNO 3 137 + 28 + 96 137 + 32 + 64 RAM=261 g = 233 g So………………..2.61 g could produce …………..? 2.33 g This is the theoretical maximum yield

3. Calculating % yield Remember: You never get 100% yield. So your answer should be less than 100% To calculate your % yield = (mass of filter paper + product)– (mass of filter paper) _________________________________________ 2.31 x100 =…………% Collect class data and compare and analyse results What is your conclusion? Can you suggest an improvement?

4. Conclusion & Improvements The classes % yield is in the range of …….. to ……g Some product is lost in the reaction because it goes through the ……………………………… To improve the experiment, next time I would use more pieces of filter paper so we lost less product Some groups had more than 100% this could be due to impurities in the tap water. To improve the experiment, next time I would use ………………………………………instead of tap water.

5. The classes % yield is in the range of (lowest) to (highest) g Some product is lost in the reaction because it goes through the filter paper To improve the experiment, next time I would use more pieces of filter paper so we lost less product Some groups had more than 100% this could be due to impurities in the tap water. To improve the experiment, next time I would use distilled water instead of tap water.