Which of the following has the smallest mass?

Options

A. 4 g of He
B. `6.022 xx 10^(23)` atoms of He
C. 1 atom of He
D. 1 mole atoms of He

Explanation

To determine which of the given options has the smallest mass, we will analyze each option step by step.

### Step 1: Analyze Option A
- **Option A** states that there are 4 grams of helium.
- This is a straightforward measurement: the mass is 4 grams.

### Step 2: Analyze Option B
- **Option B** states that there are 6.022 x 10²³ atoms of helium.
- This number (6.022 x 10²³) is known as Avogadro's number, which represents the number of atoms in one mole.
- The mass of one mole of helium is also 4 grams.
- Therefore, the mass of 6.022 x 10²³ atoms of helium is 4 grams.

### Step 3: Analyze Option C
- **Option C** asks for the mass of one atom of helium.
- We know that the mass of 6.022 x 10²³ atoms of helium is 4 grams.
- To find the mass of one atom of helium, we divide the total mass by the number of atoms:
\[ \text{Mass of one atom} = \frac{4 \text{ grams}}{6.022 \times 10^{23}} \approx 6.64 \times 10^{-24} \text{ grams} \]

### Step 4: Analyze Option D
- **Option D** also states that there are 4 grams of helium.
- Similar to Option A, the mass is 4 grams.

### Step 5: Compare the Masses
- From our analysis:
- Option A: 4 grams
- Option B: 4 grams
- Option C: \( \approx 6.64 \times 10^{-24} \) grams
- Option D: 4 grams
- The smallest mass among these options is from Option C, which is the mass of one atom of helium.

### Conclusion
- Therefore, the option with the smallest mass is **Option C**.

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