Question

The alkaline earth metal with lowest density is

• A. Be
• B. Mg
• C. Ca
• D. Sr

Hint:

While there are general trends in the periodic table, it's important to remember that exceptions can occur. Knowing specific values or the order for common properties within a group or period can be helpful.

Answer 1

The Correct Option is C

Step 1: Identify the alkaline earth metals in the options.
The options are Beryllium (Be), Magnesium (Mg), Calcium (Ca), and Strontium (Sr). These are the first four elements of Group 2.
Step 2: Recall the trend in density down Group 2.
Generally, density increases down a group due to the increasing atomic mass outweighing the increasing atomic size. However, there are exceptions.
Step 3: Consider the densities of the given alkaline earth metals.
Density of Be $\approx 1.85 \, g/cm^3$
Density of Mg $\approx 1.74 \, g/cm^3$
Density of Ca $\approx 1.55 \, g/cm^3$
Density of Sr $\approx 2.63 \, g/cm^3$
Step 4: Identify the metal with the lowest density.
Comparing the densities, Calcium (Ca) has the lowest density among the given options.
Thus, the alkaline earth metal with the lowest density is $ \boxed{Ca} $.