2019 Year 12 IB Extended Essays

Processed Data

Equation 1: Sample Calculation for Standard Deviation of Wheatgrass in 0M NaCl on Day 20: = � ∑( − � ) 2 − 1 11.7 10.8 12.3 12.4 13.4 �( −̅ ) 2 ( −̅ ) 2 0.176 1.742 0.032 0.078 1.638 3.666 = � 3.666 5 − 1 ≈ 0.957 Table 13: Mean Height of Wheatgrass grown in different concentrations of NaCl over a 20- day period NaCl Mean height of Wheatgrass/cm ( ± 0.05 cm) Days 0M 0.0068M 0.0274M 0.1095M 0.4381M 0 0 0 0 0 0 2 1.96 2.5 2.22 0.44 0.02 4 6.14 6.36 5.62 2.76 0.02 6 8 8.54 7.36 4.56 0.02 8 8.28 9.14 7.82 5.94 0.02 10 9.18 9.48 8.32 6.42 0.02 12 9.72 9.98 8.72 6.98 0.02 14 10.66 10.64 8.96 7.32 0.02 16 11.12 11.12 9.24 7.7 0.02 18 11.74 11.94 9.72 7.92 0.02 20 12.12 12.3 9.72 7.92 0.02

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