# Worksheet: Units of Nuclear Physics: the Unified Atomic Mass Unit

In this worksheet, we will practice converting between kilograms and unified atomic mass units.

**Q1: **

The mass of one atom of potassium-40 is 39.9640 u. What is the molar mass of potassium-40 in grams per mole?

**Q2: **

What is kg in unified atomic mass units? Give your answer to 3 significant figures.

**Q3: **

What is 3 u in kilograms? Give your answer to 3 significant figures.

- A kg
- B kg
- C kg
- D kg
- E kg

**Q4: **

A platinum-194 atom has a mass of 193.963 u. What is the mass of a platinum-194 atom in kilograms? Give your answer to 6 significant figures.

- A kg
- B kg
- C kg
- D kg
- E kg

**Q5: **

Uranium-238 has a molar mass of 238.051 g/mol. What is the mass of one atom of uranium-238 in unified atomic mass units?

**Q6: **

What is 12.0 µg in unified atomic mass units? Give your answer to 3 significant figures.

- A u
- B u
- C u
- D u
- E u

**Q7: **

A lithium-6 atom has a mass of 6.01512 u. What is the mass of a lithium-6 atom in kilograms? Give an answer that is precise to 6 significant figures.

- A kg
- B kg
- C kg
- D kg
- E kg

**Q8: **

A proton has a rest mass of kg. What is the rest mass of a proton in unified atomic mass units? Give an answer that is precise to 6 significant figures.

**Q9: **

A neutron has a rest mass of kg. What is the rest mass of a neutron in unified atomic mass units? Give an answer that is precise to 6 significant figures.

**Q10: **

An electron has a rest mass of . What is the rest mass of an electron in unified atomic mass units? Give an answer that is precise to 6 significant figures.

- A9.10938 u
- B1.82289 u
- C5.48580 u
- D u
- E u