Question

1. complete the statement.
2. these molecules make up
3. the same substance

different substances

Explanation:

To determine what these molecules make up, we analyze the molecular structures. The first molecule (left) has a carbonyl group (C=O) and the second (right) has a hydroxyl group (–OH) on a carbon chain. These are structural isomers (same molecular formula, different structures) of a compound with 3 carbon atoms, likely related to ketone and alcohol (or aldehyde? Wait, no—let's check the atoms. The left molecule: count C, H, O. Let's see: Left: C=3, H: let's count white (H) atoms. Left: first C (with O): 1 H, second C: 2 H, third C: 3 H? Wait, no, the left structure: C atoms (gray) are 3? Wait, left: first C (double bond O, single bond H, single bond middle C), middle C (single bonds: left C, right C, and two H), right C (three H). So formula: C₃H₆O? Wait, no, O is one. Wait, right structure: C atoms: 3? Wait, right: three C atoms, each with H: first C (3 H), middle C (2 H and –OH), third C (3 H). So formula: C₃H₈O? Wait, maybe I miscounted. Alternatively, these are isomers (same molecular formula, different structures), so they make up different substances (isomers are different compounds). So the statement "These molecules make up ____" would be "different substances" because they have the same molecular formula (same number of C, H, O) but different structures (functional groups or connectivity), so they are isomers (different compounds).

Answer:

different substances