Which of the following metals burns with brick red

Analysis

The question asks for the identification of a metal based on the characteristic color it produces when burned in a flame. This is a classic test used in qualitative analysis known as the Flame Test.

Concept: Flame Test

The flame test is used to identify the presence of certain metal ions in a compound. When these metals are heated in a Bunsen burner flame, the electrons in the metal atoms absorb energy and jump to higher energy levels. As they return to their ground state, they emit light at specific wavelengths, which appear as distinct colors.

• Sodium (Na): Produces a persistent golden-yellow flame.
• Calcium (Ca): Produces a brick-red flame.
• Lead (Pb): Does not produce a characteristic flame color (it is often associated with a greyish-white smoke).
• Magnesium (Mg): Produces a brilliant white light (often used in flares).

Step-by-Step Solution

1. Evaluate the options: We need to match each metal to its flame color.
2. Analyze Option A (Pb): Lead does not give a distinct flame color.
3. Analyze Option B (Ca): Calcium ions ($Ca^{2+}$) are well-documented in chemistry to impart a "brick-red" or "orange-red" color to a non-luminous Bunsen flame.
4. Analyze Option C (Na): Sodium is famous for its bright yellow flame.
5. Analyze Option D (Mg): Magnesium burns with a blinding white light, not red.
6. Conclusion: Based on the standard flame test results, Calcium is the correct metal.

Exam Tip

To remember these colors for your JAMB/WASSCE exams, use this simple mnemonic:

• Sodium = Sunshine (Yellow)
• Calcium = Carrot (Brick-red/Orange)
• K (Potassium) = Krimson/Lilac
• Barium = Baby green (Apple green)