Which metal has the lowest density?

Options

A. Iron
B. Gold
C. Sodium
D. Mercury

Answer

To determine which metal has the lowest density among iron, gold, sodium, and mercury, we can follow these steps:

### Step 1: Understand Density
Density is defined as mass per unit volume. It is usually expressed in grams per cubic centimeter (g/cm³). The lower the density, the lighter the metal is for a given volume.

### Step 2: Identify the Metals
The metals we are comparing are:
- Iron (Fe)
- Gold (Au)
- Sodium (Na)
- Mercury (Hg)

### Step 3: Research the Densities
We need to find the densities of these metals:
- **Iron**: Approximately 7.87 g/cm³
- **Gold**: Approximately 19.32 g/cm³
- **Sodium**: Approximately 0.97 g/cm³
- **Mercury**: Approximately 13.53 g/cm³

### Step 4: Compare the Densities
Now we can compare the densities:
- Iron: 7.87 g/cm³
- Gold: 19.32 g/cm³
- Sodium: 0.97 g/cm³
- Mercury: 13.53 g/cm³

### Step 5: Identify the Lowest Density
From the comparison, we can see that sodium has the lowest density at 0.97 g/cm³, which is significantly lower than the densities of iron, gold, and mercury.

### Conclusion
Therefore, the metal with the lowest density among the options provided is **sodium**.

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