Ethylene glycol is used as an antifreeze agent. Calculate the amount of ethylene glycol to be added to 4 kg of water to prevent it from freezing at `-6^@C`.
`(K_f " for " H_2O = 1*85 K "mole"^(-1) kg)`

Explanation

To solve the problem of calculating the amount of ethylene glycol needed to prevent 4 kg of water from freezing at -6°C, we will use the formula for depression in freezing point. Here’s a step-by-step breakdown of the solution:

### Step 1: Identify the given data
- Weight of solvent (water) = 4 kg
- Freezing point of pure water = 0°C
- Freezing point of the solution = -6°C
- \( K_f \) for water = 1.85 K kg/mol
- Molecular weight of ethylene glycol (C2H6O2) = 62 g/mol
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