To demonstrate that matter is conserved during a physical change, you want to select a procedure that ensures no matter is added or removed from the system being measured other than by the physical change itself. Among the responses given, the most appropriate one that adheres to this principle is:
1. Find the mass of a piece of ice. Let the ice melt. Find the mass of the liquid water.
This procedure represents a physical change from solid to liquid phase without any chemical alteration of the substance or loss to the environment, assuming the system is closed and there's no evaporation. Let's break down each step for clarity:
- Find the mass of a piece of ice: First, you weigh a piece of ice in a completely closed system to ensure no mass is lost as vapor.
- Let the ice melt: Allow the ice to change from its solid state to liquid at room temperature, still ensuring that the environment is closed and the water cannot evaporate.
- Find the mass of the liquid water: After the ice has completely melted into a liquid, without any loss due to evaporation, you measure the mass of the water again.
The mass should be the same before and after the physical change, confirming the principle of conservation of matter. This is because the total amount of matter (in this case, the water molecules) remains the same before and after melting; they've just changed state from solid to liquid.
Now let's consider why the other responses may not be as suitable:
2. Find the mass of a cup of water. Boil the water. Find the mass of the water that remains.
- Boiling water would convert it from liquid to gas. Unless the system is closed and captures all the water vapor (like in a sealed container), some water will escape as steam, so there will be a loss of mass.
3. Find the mass of a raw egg. Cook the egg. Find the mass of the cooked egg.
- Cooking an egg may cause some water to evaporate and it often undergoes chemical changes like protein denaturation, which although it's a physical change, the mass could seem to be reduced due to moisture loss.
4. Find the mass of an apple. Cut the apple and remove the core. Find the mass of the remaining.
- In this case, the mass will definitely change because you are physically removing a portion of the apple (the core), which is not just a physical change but also a change in the quantity of the material. This does not illustrate the conservation of mass in a closed system.
Therefore, the first response is the best way to demonstrate that matter is conserved during a physical change, provided no evaporation takes place.
Which procedure could be used to demonstrate that matter is conserved during a physical change? Use responses
Responses
Find the mass of a piece of ice. Let the ice melt. Find the mass of the liquid water.
Find the mass of a cup of water. Boil the water. Find the mass of the water that remains.
Find the mass of a raw egg. Cook the egg. Find the mass of the cooked egg.
Find the mass of an apple. Cut the apple and remove the core. Find the mass of the remaining
1 answer
1 answer