[pretend what follows is an annotated example.]

Example Item 1:

Mayer found four different bottles filled with unknown pure liquids. He made various measurements, which are displayed in the data table.

Sample	Density	Volume	Boiling Point
1	1.0 g/cm^3	6.1 cm^3	100 C
2	0.89 g/cm^3	6.1 cm^3	211 C
3	0.92 g/cm^3	10.2 cm^3	300 C
4	0.89 g/cm^3	10.2 cm^3	211 C

Mayer wondered if any of the samples were the same substance. Use the data in the table to:
1. Write a claim stating whether any of the samples could be the same substance.
2. Give at least two pieces of evidence to support your claim.
3. Provide reason(s) that the evidence you cite supports your claim.

For full credit:

• Student articulates a claim explicitly stating that Liquid 2 and 4 could be the same substance.
• Student cites evidence identifying the data pattern that the density and boiling point of Liquid 2 and 4 are the same.
• Student provides reasoning indicating that density and boiling point are characteristic properties; the same substances have the same set of characteristic properties; and Liquid 2 and 4 have the same set of characteristic properties, so they are the same substance.