(a) A sample of tetrachloroethylene, a liquid used in dry cleaning that is being phased out because of its potential to cause cancer, has a mass of 40.55 g and a volume of 25.0 mL at 25 °C. What is its density at this temperature? Will tetrachloroethylene float on water? (Materials that are less dense than water will float.)

Key Concepts

Density

Density is defined as the mass of a substance divided by its volume, typically expressed in grams per milliliter (g/mL) for liquids. It is a crucial property that helps determine how substances interact with each other, particularly whether they will float or sink in a given medium, such as water.

Buoyancy

Buoyancy refers to the ability of an object to float in a fluid, which is determined by the object's density relative to the fluid's density. An object will float if it is less dense than the fluid it is placed in; conversely, it will sink if it is denser. This principle is essential for understanding the behavior of tetrachloroethylene in water.

Phase-out of Chemicals

The phase-out of chemicals like tetrachloroethylene is often driven by health and environmental concerns, particularly their potential carcinogenic effects. Understanding the implications of using such substances is important in chemistry, as it relates to safety regulations and the search for safer alternatives in industrial applications.