To determine which substance is a solid in this description, we'll analyze the properties of each substance:
1. Object 1: Side past each other
- This description sounds like the behavior of a liquid. Liquids have particles that can slide or flow past one another while maintaining a definite volume.
2. Object 2: Are very viscous
- High viscosity indicates thickness and resistance to flow, which is another characteristic of some liquids or semi-solids. However, it still does not indicate a solid since solids are typically not described by viscosity.
3. Object 3: Forms a crystal
- Forming a crystal is a clear sign of a solid. Solids have particles arranged in a structured and repeating pattern (crystalline). This structure is very characteristic of solid substances.
4. Object 4: Spread out to fill their container
- This is a definite property of gases. Gases have particles that move freely and spread to occupy the entire volume of their container.
Given these analyses, the substance that behaves as a solid is Object 3 because forming a crystal is indicative of a solid state.
Therefore, the correct answer is Object 3.
