1. Leaf Mass Method

2. Percent Change in Mass
Remember to calculate the percent change in mass
Final Mass – Initial Mass X 100
Initial Mass
Remember a negative % change just means a loss in mass.

3. Leaf Mass Method
Cut off all the leaves on the plant and mass them. (grams)
Cut a 1 cm2 section out of 1 leaf.
Mass the 1 cm2 section.
Multiply the section’s mass by 10,000 to calculate the mass per square meter of the leaf. (g/m2)
Divide the total mass of the leaves from step 1 by the mass per square meter from step 4. This value is the leaf surface area. (m2)
Calculate the water loss per square meter of leaf surface by dividing the water loss at each reading by the leaf surface area you calculated. Record your results.
water loss (change in mass in grams)
leaf surface area
Calculate class averages for the data to use for your graphs

4. Class Data Group # Day 1 Day 2 Day 3 Day 4 Control Humidity Light Fan
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