<u>Answer:</u> The freezing point of brass is 1028.57°C
<u>Explanation:</u>
We are given:
13.4 mass percent of zinc in brass
This means that 13.4 grams of zinc is present in 100 g of brass
Mass of copper = [100 - 13.4] g = 86.6 g
Depression in freezing point is defined as the difference in the freezing point of pure solution and freezing point of solution.
The equation used to calculate depression in freezing point follows:
To calculate the depression in freezing point, we use the equation:
Or,
where,
Freezing point of pure copper = 1083°C
i = Vant hoff factor = 1 (For non-electrolytes)
= molal freezing point elevation constant = 23°C/m
= Given mass of solute (zinc) = 13.4 g
= Molar mass of solute (zinc) = 65.38 g/mol
= Mass of solvent (copper) = 86.6 g
Putting values in above equation, we get:
Hence, the freezing point of brass is 1028.57°C