If a substance cannot be separated physically and is also cannot be chemically separated, what is the substance? Use the chart below to help you answer.

The substance is an element because elements cannot be broken down further into simpler substances either physically or chemically.

| Mixture | Compound | Element |
| ------- | -------- | ------- |
| Can be physically separated | Can be chemically separated | Cannot be physically or chemically separated |

so the answer is element?

Yes, that's correct. The substance that cannot be separated physically and also cannot be chemically separated is an element.