Determine the equivalent weights of the following: K_2SO_4

Answer

To determine the equivalent weight of K₂SO₄, we will follow these steps:

### Step 1: Determine the Molecular Weight of K₂SO₄
First, we need to calculate the molecular weight of K₂SO₄ (potassium sulfate).

- Potassium (K) has an atomic weight of approximately 39 g/mol.
- Sulfur (S) has an atomic weight of approximately 32 g/mol.
- Oxygen (O) has an atomic weight of approximately 16 g/mol.

The formula for K₂SO₄ consists of:
- 2 Potassium atoms: 2 × 39 g/mol = 78 g/mol
- 1 Sulfur atom: 1 × 32 g/mol = 32 g/mol
- 4 Oxygen atoms: 4 × 16 g/mol = 64 g/mol

Now, we can sum these values to find the total molecular weight:
\[ \text{Molecular weight of K}_2\text{SO}_4 = 78 + 32 + 64 = 174 \text{ g/mol} \]

### Step 2: Determine the Valency of K₂SO₄
Next, we need to determine the valency of K₂SO₄.

K₂SO₄ dissociates in solution into:
- 2 K⁺ ions (each with a charge of +1)
- 1 SO₄²⁻ ion (with a charge of -2)

To find the valency, we consider the total positive and negative charges:
- Total positive charge = 2 × (+1) = +2
- Total negative charge = -2

The valency is determined by the magnitude of the charge, which in this case is 2.

### Step 3: Calculate the Equivalent Weight
The equivalent weight can be calculated using the formula:
\[ \text{Equivalent weight} = \frac{\text{Molecular weight}}{\text{Valency}} \]

Substituting the values we found:
\[ \text{Equivalent weight} = \frac{174 \text{ g/mol}}{2} = 87 \text{ g/equiv} \]

### Final Answer
The equivalent weight of K₂SO₄ is **87 g/equiv**.

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