do u rekon in an exam it would be worth to write for the method
i) place bottle of distilled water and a bottle of softdrink (unopened) on scales and weighed each
ii) placed each in a water bath and heated on low, re-measuring the softdrink untill there appeared to be no mass change (took water off heat aswell at exact same time when weighing soft drink). Both were heated at same temp in same conditions
iii) DID: mass(water intiially) - mass (water final) = mass H2O lost
iv) DID: mass(softdrink initially) - mass(water final) = amount of CO2 lost
--- im thinking that would be
- Reliable: do it many times, all the class got the same results
- Validity: comparing with the water gives us the ability to be calculating only the CO2 lost and not water evaporated. All experimental variables were controlled (heat) and so is a valid experimental design. We re-heated untill the mass change in the softdrink was decreasing at the rate of the water exactly. We continued re-weighing untill the softdrink decrease was the same for the water for 3 times to indicate no more CO2 was left at all
- Accuracy: scales were to 0.01g which are accurate.
Just an idea lol...do this or just stick to the normal leave bottle open untill mass is decreasing slighlty, calculate CO2 and then just say in validity: wasnt valid as didnt account for water loss...
confusing experiment yasss