Talc is a mineral that has low conductivity for heat and electricity and that is not attacked by acid. It is used as talcum powder and face powder. A sample of talc weighs 35.97 g in air and 13.65 g in mineral oil (d = 1.75 g/cm³). What is the density of talc? A)4.61 g/cm ³ B)2.82 g/cm ³ C)2.63 g/cm ³ D)2.44 g/cm ³ E)1.61 g/cm ³

Question

Quizplus · Accepted Answer

First, we can use the formula for density: density = mass / volume. We know the mass of the talc sample, so we just need to find the volume. We can use the method of displacement to find the volume. The sample weighs 35.97 g in air and 13.65 g in mineral oil, so it displaced a volume of:

(volume of mineral oil with talc) - (volume of mineral oil without talc)

= (mass of talc + mass of mineral oil with talc) - (mass of mineral oil without talc)

= (35.97 g - 13.65 g) / (1.75 g/cm3)

= 12.32 cm3

Now we can calculate the density:

density = mass / volume = 35.97 g / 12.32 cm3 = 2.92 g/cm3

The closest answer choice is B, 2.82 g/cm3.

Talc Is a Mineral That Has Low Conductivity for Heat