2019 Year 12 IB Extended Essays

Apparatus: Table 1: Materials required to conduct the experiment Quantity Apparatus

Uncertainty

± 0.025

50

Plastic Cups

1

Ruler

100g 100g 100g

Sodium Nitrate Sodium Chloride

Cotton Balls

± 0.030 3

1 1 5

Marker Pipette

250ml Volumetric Flask

1000 seeds

Triticum aestivum

2.5L

Distilled Water

Procedure: 1. Place the wheatgrass seeds in water container filled; soak for 24 hours 2. After 24 hours, place seeds in muslin cloth and leave to sprout for 12 hours then rinse and moisten seeds with water 3. Leave to germinate in muslin cloth for 12 hours ø . 4. Prepare 5 solutions of different concentrations of NaCl and of NaNO3*. 5. 50 cups were labelled with their respective concentrations of solution, consisting of 5 trials for each concentration. 6. Place 1g of cotton on each cup 7. Fill cups with 40ml of their respective concentrations of solution 8. Place 3g of germinated seeds to each of the cups

ø After the last 12 hours, seeds that sprouted roots and not shoots were chosen to ensure that the experiment was conducted in a highly controlled environment

*Refer to Appendix #1 for dilution table

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