5-PS1-2 - Measure and graph quantities to provide evidence that regardless of the type of change that occurs when heating, cooling, or mixing substances, the total weight of matter is conserved.

Clarification Statement - Examples of reactions or changes could include phase changes, dissolving, and mixing that form new substances.

Assessment Boundary - Assessment does not include distinguishing mass and weight.

5-PS1-2 - Measure and graph the weights (masses) of substances before and after a reaction or phase change to provide evidence that regardless of the type of change that occurs when heating, cooling, or combining substances, the total weight (mass) of matter is conserved.

Clarification Statement - Assume that reactions with any gas production are conducted in a closed system.

Assessment Boundary - Distinguishing mass and weight is not expected in state assessment.