All carbonates in alkali metals are

Options

A. 1
B. 7
C. 4
D. 2

Explanation

To solve the question "All carbonates in alkali metals are," we need to analyze the properties of carbonates formed by alkali metals. Here’s a step-by-step breakdown of the solution:

### Step 1: Identify Alkali Metals
The alkali metals include Lithium (Li), Sodium (Na), Potassium (K), Rubidium (Rb), Caesium (Cs), and Francium (Fr).

**Hint:** Remember that alkali metals are located in Group 1 of the periodic table.

### Step 2: Understand the Electron Configuration
Alkali metals have a general electron configuration of \( ns^1 \), where \( n \) represents the principal quantum number corresponding to the outermost shell. For example:
- Lithium (Li): \( 1s^2 2s^1 \)
- Sodium (Na): \( 1s^2 2s^2 2p^6 3s^1 \)
- Potassium (K): \( 1s^2 2s^2 2p^6 3s^2 3p^6 4s^1 \)

**Hint:** The outermost electron in alkali metals is always in the s-orbital.

### Step 3: Analyze Carbonate Formation
When alkali metals react with carbon dioxide (\( CO_2 \)), they form carbonates (\( M_2CO_3 \)), where \( M \) represents the alkali metal. The general formula for carbonates of alkali metals is \( M_2CO_3 \).

**Hint:** Carbonates consist of the carbonate ion \( CO_3^{2-} \), which combines with two alkali metal ions.

### Step 4: Determine the Solubility of Carbonates
All alkali metal carbonates are soluble in water. This is a characteristic property of alkali metal compounds.

**Hint:** Solubility is a key property to consider when discussing compounds of alkali metals.

### Step 5: Conclusion
Thus, the answer to the question "All carbonates in alkali metals are" is that they are soluble in water.

### Final Answer:
All carbonates in alkali metals are soluble in water.

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