# Sophia Coulter - Osmosis_Water Potential Lab.pdf - Osmosis...

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Osmosis, water potential, graphing and more! Mr. Bakland made six different solutions, each containing various concentrations of sucrose, but he forgot to label each one! It is your group’s task to solve the mystery of which solution represents each of the possible molar concentrations: 0.0 M sucrose, 0.2 M sucrose, 0.4 M sucrose, 0.6 M sucrose, 0.8 M sucrose, and 1.0 M sucrose by measuring the change in the mass of carrots and potato samples. Statistics Background: Standard Deviation measures how spread out the data is from the mean. o A lower standard deviation means that the data is closer to the mean, and that there is a greater likelihood that the independent variable is causing the changes in the dependent variable. o A higher standard deviation means that the data is more spread out from the mean, and most likely other factors other than the independent variable are influencing the dependent variable. Standard Error indicates how well the mean of a sample estimates the true mean of a population. Background information Water moves through membranes by diffusion; this process is called osmosis. Like solutes, water moves down its concentration gradient. Water moves from areas of high water potential (high water concentration) and low solute concentration to areas of low water potential (low water concentration) and high solute concentration. In plants with a cell wall, osmosis is affected not only by the solute concentration but also by the resistance to water movement in the cell by the cell wall. This resistance is called turgor pressure (the physical pressure exerted on the cell).
Hypothesis: If the potato decreases in mass, then it is in a hypertonic solution, because the environment outside of the potato has a higher solute concentration than the interior of the potato, so water moved outside the potato to regain equilibrium.