Question

matter interactions unit test
which procedure could be used to demonstrate that matter is conserved during a physical change? (1 point)
find the mass of an apple. cut the apple and remove the core. find the mass of the remaining apple.
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

Explanation:

• When ice melts (a physical change), it changes from solid to liquid. According to the law of conservation of matter, the mass of the ice (solid - physical state) should be equal to the mass of the liquid water (liquid - physical state) after melting as no matter is added or removed from the system (assuming no evaporation which is negligible in this simple case).
• In the apple - cutting example, the core is removed, so matter is taken out of the system, which does not demonstrate conservation of matter during a physical change.
• When boiling water, some water turns into vapor and escapes into the air (if not in a closed container), so the mass of the remaining water is not equal to the initial mass of the water, not demonstrating conservation of matter during a physical change.
• When cooking an egg, a chemical change occurs (denaturation of proteins etc.), so it is not a physical change demonstration.

Answer:

Find the mass of a piece of ice. Let the ice melt. Find the mass of the liquid water.