Which One of the Following Represents a Chemical Change

question 148

Multiple Choice

Which one of the following represents a chemical change

• A) boiling water to form steam
• B) burning a piece of coal
• C) heating lead until it melts
• D) mixing iron filings and sand at room temperature
• E) breaking glass

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Definitions:

Nodes

Points along a standing wave where the wave amplitude is zero, or points in an atom where the probability of finding an electron is zero.

π Molecular Orbitals

Orbitals formed by the overlap of p orbitals on adjacent atoms, significant in determining the bonding and properties of molecules.

Electron Density

Refers to the probability distribution of electrons in a chemical species; higher density regions indicate a greater likelihood of electron presence.

Internuclear Axis

The imaginary line that runs through the nuclei of two atoms bonded together, defining the direction of the bond.