Which of the following is an example of simple diffusion? A sugar cube dissolves in coffee_ Eating salty popcorn makes people’s lips dry: Vegetables placed in fresh water firm up. Strawberries placed in sugar become syrupy: Salting meat serves as a preservative:
The Correct Answer and Explanation is:
The correct answer is: A sugar cube dissolves in coffee.
Explanation:
Simple diffusion is the process by which molecules move from an area of high concentration to an area of low concentration, typically without the need for energy input or the assistance of carrier proteins. This movement is driven by the concentration gradient.
In the case of the sugar cube dissolving in coffee, the sugar molecules are initially concentrated in the sugar cube. When the cube is placed in the coffee, the sugar molecules diffuse from the area of high concentration (the cube) into the surrounding liquid (the coffee) where the concentration is lower. This is a classic example of simple diffusion, as the molecules move freely and without the need for energy or special channels.
Now, let’s break down the other options:
- Eating salty popcorn makes people’s lips dry – This is an example of osmosis and dehydration, not simple diffusion. Osmosis is the movement of water across a semipermeable membrane, often in response to a difference in solute concentration, as in the case of salt drawing moisture from the body tissues.
- Vegetables placed in fresh water firm up – This is an example of osmosis. The vegetables are likely absorbing water from the fresh water to balance out the concentration of solutes inside their cells. Osmosis involves the movement of water, not simple diffusion.
- Strawberries placed in sugar become syrupy – This is an example of osmosis as well. The sugar draws water out of the strawberries, causing them to release moisture, forming a syrup.
- Salting meat serves as a preservative – This is an example of osmotic pressure. Salt causes water to move out of the meat, making it dry and less hospitable to bacteria, thus preserving the meat. It is not simple diffusion.
In conclusion, the sugar cube dissolving in coffee is the only process that illustrates simple diffusion.
