Which one of the following cations gives a brick red flame by flame test

Options

A. `Ba^(2+)`
B. `Sr^(2+)`
C. `Ca^(2+)`
D. `Zn^(2+)`

Answer

To determine which cation gives a brick red flame during a flame test, we can follow these steps:

### Step 1: Understand the Flame Test
The flame test is a qualitative analysis technique used to identify the presence of certain metal ions based on the color of the flame produced when the metal is heated. Different metal cations emit characteristic colors when subjected to a flame.

### Step 2: Identify Common Cations and Their Flame Colors
We need to recall the flame colors associated with various metal cations:
- **Barium (Ba²⁺)**: Light yellow or greenish flame
- **Strontium (Sr²⁺)**: Crimson red flame
- **Calcium (Ca²⁺)**: Brick red flame
- **Zinc (Zn²⁺)**: Different color (usually bluish-green)

### Step 3: Focus on the Question
The question specifically asks for the cation that gives a brick red flame. From our knowledge of flame colors:
- Calcium (Ca²⁺) is known to produce a brick red flame.

### Step 4: Conclusion
Based on the information gathered, the cation that gives a brick red flame during a flame test is **Calcium (Ca²⁺)**.

### Final Answer
**Calcium (Ca²⁺)** gives a brick red flame by flame test.

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