A student adds 10 grams of salt to 90 grams of water in a cup. After stirring, all the salt dissolves and the mixture looks like plain water.

Students placed ice cubes in a sealed container and recorded the mass before and after the ice melted.

Mr. Lincoln’s class is making five pounds of slime.

Luis and his sister are baking bread.

A student conducted four small experiments to observe how the mass of substances changes after heating, cooling, or mixing.

A student places 5 grams of baking soda into a 250 mL flask, then adds 50 mL of vinegar.