What does `i mol kg^(-1) KCl` solution signifies?

Options

A. 1 mole of KCl is dissolved in 1 kg of water
B. 1 mole of KCl is dissolved in 1 L of water
C. 1 mole of KCl is dissolved in 1 mL of water
D. None of the above

Answer

To understand what `i mol kg^(-1) KCl` solution signifies, we can break it down into steps:

### Step 1: Understanding the Units
The notation `i mol kg^(-1)` indicates that we are dealing with a concentration measurement known as molality. The unit `kg^(-1)` signifies that the concentration is based on the mass of the solvent (in kilograms).

**Hint:** Remember that molality is defined as the number of moles of solute per kilogram of solvent.

### Step 2: Defining Molality
Molality (m) is defined as the number of moles of solute (in this case, KCl) dissolved in one kilogram of solvent. Therefore, `i mol kg^(-1)` means that there are `i` moles of KCl for every 1 kg of solvent.

**Hint:** Molality is different from molarity, which is based on the volume of the solution rather than the mass of the solvent.

### Step 3: Understanding KCl
KCl stands for potassium chloride, which is a common ionic compound. When KCl is dissolved in water, it dissociates into potassium ions (K⁺) and chloride ions (Cl⁻).

**Hint:** The dissociation of KCl in water can affect properties like boiling point and freezing point, which is important in colligative properties.

### Step 4: Implications of the Solution
When we say `i mol kg^(-1) KCl` solution, it implies that the solution has a specific concentration of KCl, which can be used in various chemical calculations, including those involving colligative properties, such as boiling point elevation and freezing point depression.

**Hint:** The concentration of the solution can influence its physical and chemical properties, which is crucial in many applications.

### Summary
In summary, `i mol kg^(-1) KCl` signifies a molal solution of potassium chloride, indicating that there are `i` moles of KCl dissolved in one kilogram of solvent. This is a key concept in understanding solution chemistry and its applications.