Substances whose density is ______the density of water, sink in water.

Explanation

To solve the question "Substances whose density is ______ the density of water, sink in water," we need to understand the relationship between density, buoyancy, and whether an object will sink or float in water.

### Step-by-Step Solution:

1. **Understanding Density**:
- Density is defined as mass per unit volume. It is usually expressed in grams per cubic centimeter (g/cm³) or kilograms per cubic meter (kg/m³).
- Water has a density of approximately 1 g/cm³ (or 1000 kg/m³).

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