Final answer:
Mercury(II) oxide is a red solid that decomposes upon heating into liquid mercury and oxygen gas, a process that is indicative of a binary compound decomposition reaction requiring heat.
Step-by-step explanation:
Decomposition of Mercury(II) Oxide
Mercury(II) oxide, also known as mercuric oxide, is a compound that can be decomposed by heating. When subjected to temperatures above 500°C, this red solid breaks down into its constituent elements: liquid mercury and oxygen gas. This decomposition process is an example of a chemical change where a more complex substance is broken down into simpler substances.
Decomposition reactions, like that of mercury(II) oxide, typically require an input of energy in the form of heat, light, or electricity. In the case of mercury(II) oxide, heat is the form of energy that initiates the decomposition. This compound's breakdown is representative of binary compounds (those composed of two elements) decomposition, where the compound is reduced to its elemental constituents.
The reaction can be represented by the equation: HgO → Hg + O2. Upon decomposition, the initial orange-red color of mercury(II) oxide changes to the silver color of liquid mercury. This color change indicates that the reaction has occurred, transforming a solid compound into a liquid and a gas.