Question

what do these two changes have in common? boiling an egg ice crystals forming on a window select all that apply. both conserve mass. both are only physical changes. both are caused by cooling. both are chemical changes.

Explanation:

Boiling an egg is a chemical change as the proteins in the egg denature. Ice - crystals forming on a window is a physical change (deposition). All chemical and physical changes conserve mass according to the law of conservation of mass. Boiling an egg is caused by heating, not cooling, and ice - crystals forming is caused by cooling.

Answer:

A. Both conserve mass.