Which transition metal has lowest density ?

Options

A. Sc
B. Ti
C. Zn
D. La

Answer

To determine which transition metal has the lowest density, we can follow these steps:

### Step 1: Identify the transition metals in question
We are considering Scandium (Sc), Titanium (Ti), and Zinc (Zn), which are all transition metals in the 4th period of the periodic table.

### Step 2: Understand the factors affecting density
Density is defined as mass per unit volume (Density = Mass/Volume). Therefore, we need to consider both the mass and the volume of the metals.

### Step 3: Analyze the trend in size and mass
- As we move down a group in the periodic table, the atomic size increases due to the addition of electron shells. However, the mass also increases because more protons and neutrons are added.
- When moving from left to right across a period, the atomic size generally decreases while the mass increases.

### Step 4: Compare the densities of Scandium, Titanium, and Zinc
- Scandium has a lower atomic mass compared to Titanium and Zinc, but it is also smaller in size.
- As we analyze the densities:
- Scandium (Sc) has a density of approximately 2.985 g/cm³.
- Titanium (Ti) has a density of approximately 4.506 g/cm³.
- Zinc (Zn) has a density of approximately 7.134 g/cm³.

### Step 5: Conclusion
From the above analysis, we can conclude that Scandium has the lowest density among the three transition metals considered.

### Final Answer
**Scandium (Sc) has the lowest density among the transition metals mentioned.**

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