Final answer:
To calculate the mass of magnesium that displaces 84.2 mL of water, multiply the density of magnesium (1.74 g/cm3) by the volume of water displaced (84.2 mL). The mass of magnesium metal that displaces 84.2 mL of water at 25 °C is 146.508 grams.
Step-by-step explanation:
The density of magnesium metal is 1.74 g/cm3 at 25 °C. If a student wants to calculate the mass of magnesium that displaces 84.2 mL of water at 25 °C, they would use the formula for density (ρ) which is mass (m) divided by volume (V). Here, we have the density of magnesium and the volume of water displaced. So the calculation is:
- Density of magnesium (ρ) = 1.74 g/cm3
- Volume of water displaced (V) = 84.2 mL (which is equivalent to 84.2 cm3)
To find the mass of magnesium (m), we multiply the density of magnesium by the volume of water displaced:
m = ρ × V
m = 1.74 g/cm3 × 84.2 cm3
m = 146.508 g
Therefore, the mass of magnesium metal that will displace 84.2 mL of water at 25 °C is 146.508 grams.