Stoichiometry and titrations
Science A2
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A2 Science Stoichiometry and titrations
Screen 1: Dissolved oxygen is vital for a healthy River Thames. When untreated sewage enters the River, this creates a ‘biological oxygen demand’. Aerobic bacteria thrive on the nutrients in the sewage, using up dissolved oxygen as they multiply.
Screen 2: Work out how 1 mol O2 is represented at each stage in the test so you can make the final calculation!
Screen 3.1: Click the next arrow to reveal how to ‘fix’ the O2.
Screen 3.2: Click the next arrow for Stage 2.
Screen 4.1: Click the next arrow to reveal how to release I2.
Screen 4.2: Click the next arrow to reveal how to release I2.
Screen 4.3: Click the next arrow for Stage 3.
Screen 5.1: Click the next arrow to reveal how to use titrate to measure I2.
Screen 5.2: Click the next arrow to review Winkler Test kits.
Slide 6: Use your calculations to identify the best kit. Identify features that enable a titration with good ‘resolving power’ or accuracy.