120 likes | 140 Views
Osmosis Lab. Definition of Osmosis. WATER moves from an area of HIGH to LOW concentration across a semipermeable membrane. Research Background Knowledge. Osmosis is the diffusion of water across a semipermeable membrane. Water moves from an area of high to low concentration.
E N D
Definition of Osmosis WATER moves from an area of HIGH to LOW concentration across a semipermeable membrane.
ResearchBackground Knowledge • Osmosis is the diffusion of water across a semipermeable membrane. • Water moves from an area of high to low concentration. • The size of the substance in relationship to the size of the openings (pores) in the membrane will impact diffusion/osmosis. • Cells will either remain the same, swell or shrink as a result of osmosis.
Problem/Purpose • What effect will distilled water and salt water have on the mass of a potato slice? • Increase in mass – water going in • Decrease in mass – water coming out
Hypothesis • The potato slice in the distilled water will increase in mass and the potato slice in the salt water will decrease in mass. • The potato slice in the salt water will increase in mass the potato slice in distilled water will decrease in mass. DON’T FORGET YOUR REASONING . . . YOUR “BECAUSE” STATEMENT.
Independent What did we change? What experimental condition was under our control? Type of Water Dependent What are we measuring? What data we are collecting? Mass of the potato slice Variables
Control Group Did we have one? Experimental Group Potato in salt water and distilled water The Experiment
Constants • What did we keep the same to control the number of variables introduced into the experiment? • The potato • Volume of liquid in Petri dish • Equipment as directed in “Materials” list • Method used to set up the experiment • Method used to collect data
% of Change(increase or decrease) • Difference ÷ Mass Before × 100 • Mass Before – 4 grams • Mass After – 6 grams • Difference in Mass – 2 grams • 2 g ÷ 4 g = 0.50 × 100 = 50%
Graph • Bar graph with 4 total bars • Should have a before and after bar for each type of water next to one another • Label both x and y axis • Title should contain both independent and dependent variable • Key
Conclusion • Do not use first person • Restate the purpose • Restate the hypothesis • Summarize the procedures and results • Discuss any errors • Discuss any future extensions for experiments in the future