Question

what do these two changes have in common? bleaching clothes beating an egg select all that apply. both are changes of state. both conserve mass. both are caused by cooling. both are only physical changes.

Explanation:

To solve this, we analyze each option:

Analyzing "Both are changes of state":

• Bleaching clothes (a chemical change, e.g., using bleach to break down stains) and beating an egg (a physical change, mixing/whipping) do not involve a change of state (like solid → liquid → gas). So this is incorrect.

Analyzing "Both conserve mass":

• According to the law of conservation of mass, in any physical or chemical change, the total mass of reactants/products remains constant. Both bleaching (chemical) and beating an egg (physical) follow this law. So this is correct.

Analyzing "Both are caused by cooling":

• Bleaching is typically a chemical reaction (not caused by cooling), and beating an egg is a mechanical action (not cooling). So this is incorrect.

Analyzing "Both are only physical changes":

• Bleaching clothes involves a chemical reaction (bleach reacts with stains), so it is a chemical change. Beating an egg is a physical change (mixing, no new substance). So this is incorrect.

• "Both are changes of state" is wrong (no state change).
• "Both conserve mass" is correct (law of conservation of mass applies to both physical/chemical changes).
• "Both are caused by cooling" is wrong (neither is caused by cooling).
• "Both are only physical changes" is wrong (bleaching is chemical).

Answer:

Only the option "Both conserve mass" is correct. So the correct choice is:
Both conserve mass.