Co-ordination number for sodium metal is

Options

A. 11
B. 12
C. 8
D. 10

Answer

To determine the coordination number of sodium metal, we will follow these steps:

### Step 1: Understand the concept of coordination number
The coordination number is defined as the number of atoms, ions, or molecules that a central atom or ion can bond with in a complex or crystal structure. In the case of sodium metal, we are interested in how many negatively charged ions surround a sodium ion.

**Hint:** Recall that coordination number refers to the number of surrounding particles around a central ion.

### Step 2: Identify the charge of sodium
Sodium (Na) is an alkali metal that typically loses one electron to form a positively charged ion (Na⁺). This means that in a crystal lattice or complex, Na⁺ will be surrounded by negatively charged ions.

**Hint:** Remember that sodium loses one electron to become Na⁺.

### Step 3: Determine the surrounding ions
In a solid state, sodium can coordinate with various anions (negatively charged ions). The most common coordination number for sodium in a crystalline structure is influenced by the size and charge of the surrounding anions.

**Hint:** Think about common anions that could surround sodium in a crystal lattice.

### Step 4: Analyze the coordination number
For sodium, the coordination number can vary depending on the arrangement of the ions. However, it is generally accepted that the coordination number of sodium in solid sodium metal is 8. This means that there are 8 surrounding anions around each sodium ion in the crystal structure.

**Hint:** Consider the common coordination numbers that are typically observed in ionic compounds.

### Step 5: Conclusion
Thus, the coordination number of sodium metal is 8.

**Final Answer:** The coordination number for sodium metal is 8.

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