The actual mass of a proton is ............g.

Answer

To find the actual mass of a proton, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Protons**:
- Protons are positively charged particles found in the nucleus of an atom. They, along with neutrons, make up the nucleus and are collectively referred to as nucleons.

2. **Relation to Hydrogen Atom**:
- A hydrogen atom consists of one proton and one electron. Since the mass of the electron is negligible compared to that of the proton, we can approximate the mass of the hydrogen atom to be essentially the mass of the proton.

3. **Mass of Proton**:
- The actual mass of a proton is approximately equal to the mass of a hydrogen atom. The value is given as:
\[ \text{Mass of proton} = 1.676 \times 10^{-24} \text{ g} \]

4. **Conclusion**:
- Therefore, the actual mass of a proton is \( 1.676 \times 10^{-24} \) grams.

### Final Answer:
The actual mass of a proton is \( 1.676 \times 10^{-24} \) g.

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