The Law of Conservation of Matter

The video explains the law of conservation of mass, illustrating it with examples like boiling water and rusting copper pipes. It emphasizes that mass remains constant during physical and chemical changes, as demonstrated by balanced chemical equations. Everyday examples, such as digestion, further highlight this principle, showing that matter is neither created nor destroyed but transformed.

What happens to the mass of water when it boils and turns into steam?

• The mass decreases because steam is less dense.

• The mass increases because steam expands.

• The mass remains the same because of conservation of mass.

• The mass disappears as steam is invisible.

What is a common misconception about gases like steam?

• They have no mass.

• They are denser than liquids.

• They are visible.

• They are heavier than solids.

Why is it important to balance chemical equations?

• To ensure the reaction is fast.

• To verify that no atoms are created or destroyed.

• To make the reaction more efficient.

• To reduce the energy required for the reaction.

What happens to the atoms during a chemical reaction according to the conservation of matter?

• They are destroyed.

• They are created.

• They disappear.

• They are rearranged.

What causes the increase in mass of a rusting copper pipe?

• The pipe loses electrons.

• The pipe absorbs moisture from the air.

• Oxygen atoms from the air bond with copper.

• The copper atoms expand.

What is the role of oxygen in the rusting process?

• It reduces the mass of the pipe.

• It bonds with copper to form rust.

• It evaporates from the surface.

• It forms a protective layer.

How does the law of conservation of matter apply to digestion?

• Food is completely converted to waste.

• Food mass is lost as energy.

• Food mass is stored as fat.

• Food is broken down and used to build cells and provide energy.