Non - metals usually have desnities ______than `1 g // cm^(3)` . Therefore, they float on water .

Options

A. more
B. less
C. equal
D. Both (a) and (b)

Answer

To solve the question regarding the densities of non-metals and their ability to float on water, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Density**:
- Density is defined as the mass of a substance divided by its volume. It is usually expressed in grams per cubic centimeter (g/cm³).

2. **Density of Water**:
- The density of water is approximately 1 g/cm³. This is a crucial reference point for determining whether a substance will float or sink in water.

3. **Condition for Floating**:
- For any object to float on a liquid, its density must be less than the density of that liquid. Therefore, for a substance to float on water, its density must be less than 1 g/cm³.

4. **Non-Metals and Their Densities**:
- Non-metals generally have densities that are less than 1 g/cm³. This means that they can float on water.

5. **Conclusion**:
- Since non-metals usually have densities less than 1 g/cm³, they will float on water.

### Final Answer:
Non-metals usually have densities **less** than 1 g/cm³. Therefore, they float on water.

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