Question

Which procedure could be used to demonstrate that matter is conserved during a chemical change or reaction?

Find the mass of a stick of butter. Heat the butter until it melts. Find the mass of the melted butter.

Find the mass of a log. Burn the log until it turns to ash and smoke. Find the mass of the ash.

Find the mass of a piece of paper. Tear the paper into smaller pieces. Find the mass of the pieces.

Find the mass of an acid and a base. Combine them to produce water and a salt. Find the mass of the water and salt.

Answer 1

To demonstrate that matter is conserved during a chemical change or reaction, the best procedure would be:

**Find the mass of an acid and a base. Combine them to produce water and a salt. Find the mass of the water and salt.**

This procedure is ideal because it involves a chemical reaction where new substances (water and salt) are formed from the reactants (the acid and base). According to the law of conservation of mass, the total mass of the reactants should equal the total mass of the products. By measuring the mass of the reactants before the reaction and the mass of the products afterward, you can effectively demonstrate that matter is conserved during the chemical change.

The other procedures mentioned either involve physical changes (melting butter and tearing paper) or incomplete mass measurement (burning a log, where gases are released into the air and not measured).