* Compound: A compound is formed by two or more different elements chemically bonded together. Many compounds are white crystalline solids, like sugar (sucrose), table salt (sodium chloride), and baking soda (sodium bicarbonate).

* Element: An element is a pure substance made up of only one type of atom. Some elements exist as white crystalline solids, like phosphorus, sulfur, and arsenic.

To determine if a white crystalline solid is a compound or an element, you would need to perform further analysis:

* Chemical analysis: Identifying the specific elements present and their ratios would indicate if it's a compound or an element.

* Physical properties: The melting point, boiling point, and solubility can help distinguish between different substances.

* Spectroscopy: Techniques like infrared (IR) spectroscopy and nuclear magnetic resonance (NMR) can provide detailed information about the structure and bonding in the solid.

Without additional information, it's impossible to definitively say whether a white crystalline solid is a compound or an element.