Background: Diffusion is the movement of molecules from an area of high concentration of the molecules to an area with a lower concentration. For cell transport, diffusion is the movement of small molecules across the cell membrane. The difference in the concentrations of the molecules in the two areas is called the concentration gradient . The kinetic energy of the molecules results in random motion, causing diffusion. In simple diffusion, this process proceeds without the aid of a transport protein. it is the random motion of the molecules that causes them to move from an area of high concentration to an area with a lower concentration.

Situation: Beth was getting ready for her date. The last thing she needed to do was put on some perfume and grab her sweater. She sprayed some perfume on then walked across the room to get her sweater. Beth was surprised she could smell the perfume so strongly across the room.

Question: Did the perfume molecules still or moving.

Situation: Beth was getting ready for her date. The last thing she needed to do was put on some perfume and grab her sweater. She sprayed some perfume on then walked across the room to get her sweater. Beth was surprised she could smell the perfume so strongly across the room.

Question: Did the perfume molecules stay where Beth sprayed them or spread out?

Situation: Beth was getting ready for her date. The last thing she needed to do was put on some perfume and grab her sweater. She sprayed some perfume on then walked across the room to get her sweater. Beth was surprised she could smell the perfume so strongly across the room.

Question: Is the space between molecules increasing or decreasing as the move?

Situation: Beth was getting ready for her date. The last thing she needed to do was put on some perfume and grab her sweater. She sprayed some perfume on then walked across the room to get her sweater. Beth was surprised she could smell the perfume so strongly across the room.

Question: Are the molecules moving in a pattern around the room or randomly?

Situation: Beth was getting ready for her date. The last thing she needed to do was put on some perfume and grab her sweater. She sprayed some perfume on then walked across the room to get her sweater. Beth was surprised she could smell the perfume so strongly across the room.

Question: When Beth first sprayed the perfume was was the concent4ration orf perfume higher near her or across the room?

Situation: Beth was getting ready for her date. The last thing she needed to do was put on some perfume and grab her sweater. She sprayed some perfume on then walked across the room to get her sweater. Beth was surprised she could smell the perfume so strongly across the room.

Question: When Beth first sprayed the perfume was was the concent4ration orf perfume lower near her or across the room?

Situation: Jeff knows smoking isn't good for you but he still loves the the smell of fresh pipe tobacco. Some of his fondest childhood memories are of sitting on the porch talking to his grandpa as he smoked his pipe. Jeff remembers being fascinated by the smoke as it billowed out of the pipe and wafted across the porch.

Question: Was the concentration of smoke molecules highest near the pipe or on the other side of the porch?

Situation: Jeff knows smoking isn't good for you but he still loves the the smell of fresh pipe tobacco. Some of his fondest childhood memories are of sitting on the porch talking to his grandpa as he smoked his pipe. Jeff remembers being fascinated by the smoke as it billowed out of the pipe and wafted across the porch.

Question: Did the smoke move in a pattern or randomly?

Situation: Jeff knows smoking isn't good for you but he still loves the the smell of fresh pipe tobacco. Some of his fondest childhood memories are of sitting on the porch talking to his grandpa as he smoked his pipe. Jeff remembers being fascinated by the smoke as it billowed out of the pipe and wafted across the porch.

Question: Was it kinetic or thermal energy that moved the smoke?

Situation: Jeff knows smoking isn't good for you but he still loves the the smell of fresh pipe tobacco. Some of his fondest childhood memories are of sitting on the porch talking to his grandpa as he smoked his pipe. Jeff remembers being fascinated by the smoke as it billowed out of the pipe and wafted across the porch.

Question: Was the concentration of smoke molecules lowest near the pipe or on the other side of the porch?

Situation: Jeff knows smoking isn't good for you but he still loves the the smell of fresh pipe tobacco. Some of his fondest childhood memories are of sitting on the porch talking to his grandpa as he smoked his pipe. Jeff remembers being fascinated by the smoke as it billowed out of the pipe and wafted across the porch.

Question: Is the smoke thicker or thinner across the porch?

Situation: Jeff knows smoking isn't good for you but he still loves the the smell of fresh pipe tobacco. Some of his fondest childhood memories are of sitting on the porch talking to his grandpa as he smoked his pipe. Jeff remembers being fascinated by the smoke as it billowed out of the pipe and wafted across the porch.

Question: Is the smoke thicker or thinner right above the pipe?

Situation: Jeff knows smoking isn't good for you but he still loves the the smell of fresh pipe tobacco. Some of his fondest childhood memories are of sitting on the porch talking to his grandpa as he smoked his pipe. Jeff remembers being fascinated by the smoke as it billowed out of the pipe and wafted across the porch.

Question: Is the smoke have more kinetic energy near the pipe or farther away?