As determined by the reaction rate constant, which catalyst from baker’s yeast, baking powder, and manganese (IV) oxide is the most effective at catalyzing the decomposition of 3% hydrogen peroxide?
Chemistry
IA
7
HL
How does changing the concentration of copper (II) sulphate solution (0.2M, 0.4M, 0.6M, 0.8M, and 1.0M) affect the voltage of a copper-magnesium galvanic cell at constant concentration of magnesium sulphate solution, temperature of copper sulphate and magnesium sulphate solution, and concentration of potassium nitrate solution, measured by a voltmeter?
Chemistry
IA
6
SL
How do the steeping times (30, 60, 90, 120 and 150 seconds) of tea affect its caffeine content using dichloromethane in a separating funnel?
Chemistry
IA
7
SL
How does temperature (5.0ºC, 10.0ºC, 15.0ºC, 20.0ºC, 25.0ºC, 30.0ºC, 35.0ºC, 40.0ºC) affect the concentration of dissolved oxygen (mg/dm3) in 20.00cm3 of deionised water, measured using Winkler's titration method?
Chemistry
IA
7
HL
How does the boiling time (0.00, 240.00, 480.00, 720.00, 960.00, 1200.00 seconds) affect the amount of ionic calcium (in mg) in cow’s milk determined using Ethylenediaminetetraacetic acid (EDTA) complexometric back titration using Eriochrome Black T indicator?
Chemistry
IA
7
HL
Investigation into how varied temperature (20℃, 30℃, 40℃, 50℃, 60℃, 70℃) affect the bleaching capacity of sodium hypochlorite in removing protein-based stains (egg-yolk) from 100% cotton fabric, measured by the ΔE value obtained using the Color Identifier Colorimeter app?
Chemistry
IA
6
SL
How does temperature (ranging from 10℃ to 50℃) affect the rate of the iodine clock reaction, and what is the relationship between temperature and reaction rate? Specifically, how can the reaction rate be determined from the time taken to reach the blue-black endpoint, and how can this data be analysed using the Arrhenius equation to estimate the activation energy of the reaction?
Chemistry
IA
5
HL
How does heating different cooking oils (olive oil, sunflower oil, and canola oil) at temperatures of (40°C, 60°C and 80°C) for 30 minutes affect their acid value and free fatty acid content, as determined by acid-base titration?
Chemistry
IA
6
SL
What is the effect of the cooking temperature (10, 30, 60, 80, 100 ºC) of Brassica rapa subsp. chinensis on its content of calcium ions (mg), as measured by the titration volume of 0.01M EDTA (Ethylenediaminetetraacetic acid) required to completely react with calcium (II) ions in a solution of Brassica rapa subsp. chinensis after cooking it for 5 minutes?
Chemistry
IA
6
SL
How Do Different Agar Adsorbents (Agar-agar, Agar With Activated Carbon, Agar With Iron(III) Oxide (Fe2O3), Agar With Zinc Oxide (ZnO) and Agar With Manganese(IV) Oxide (MnO2)) Affect the Concentration (mg/dm3) of Methylene Blue Dye in Water After 24 Hours?
Chemistry
IA
6
HL