Question

An unknown metal weighing 78.8 g is added to a 100.00 mL graduated flask. A total of 80.97 g of CCl₄ (density = 1.590 g/mL) is required to bring the level of the mixture up to the 100.00 mL mark in the flask. Calculate the density of the metal.

a. 7.89 g/mL
b. 8.10 g/mL
c. 6.88 g/mL
d. 9.12 g/mL

Answer 1

Upon calculation, the density of the unknown metal by dividing the mass (78.8 g) by the calculated volume (49.08 mL) gives 1.605 g/mL, which does not match the answer choices provided. There may be an error in the calculation or in the presented options.

Step-by-step explanation:

To calculate the density of the unknown metal, we should consider the mass of the metal and the volume it occupies. The mass of CCl₄ needed to fill up the graduated flask to 100.00 mL gives us a clue about the volume occupied by the metal.

The mass of CCl₄ is 80.97 g, and since the density of CCl₄ is 1.590 g/mL, the volume of CCl₄ used is:

Volume = Mass / Density
Volume = 80.97 g / 1.590 g/mL
Volume = 50.92 mL

Since the flask was filled to 100.00 mL with the addition of CCl₄, the volume occupied by the metal must be 100.00 mL - 50.92 mL = 49.08 mL.

The density of the metal can now be calculated as follows:

Density = Mass / Volume
Density = 78.8 g / 49.08 mL
Density = 1.605 g/mL

However, this calculated density does not match with any of the options provided (a. 7.89 g/mL, b. 8.10 g/mL, c. 6.88 g/mL, d. 9.12 g/mL), suggesting there might be a mistake in the calculation or in the provided options.