🔍 Key Concepts

• How mechanical filters actually separate contaminants (think about size and physical state). • The difference between dissolved contaminants and suspended particles in lube oil. • Which contaminants change the chemical properties of the oil instead of just being solid debris.

💭 Think About

• Ask yourself: which of these contaminants is likely to be in the form of very fine solid particles that can be trapped by a filter, and which might be mixed or dissolved in the oil? • Consider what a typical lube oil filter on an engine is designed to remove: is it mainly for solids, liquids, or chemical byproducts? • Think about which of these contaminants might require separation (like a purifier or centrifuge) or chemical treatment instead of simple filtration.

✅ Before You Answer

• Identify which options are primarily solid particles versus liquids or dissolved substances. • Recall that standard lube oil filters are not the same as centrifuges or purifiers – they mainly catch particulates. • Before choosing, ask: "Would this contaminant pass through the tiny pores of a filter because it is actually mixed or dissolved in the oil?"