The phrase "a certain chunk" is correct and usable in written English.
It can be used when referring to a specific portion or segment of something, often in a vague or unspecified manner.
Example: "I need to analyze a certain chunk of data to identify trends in the results."
Alternatives: "a specific portion" or "a particular segment".
But it will carve away a certain chunk of the BlackBerry's market.
But like the SoundExchange numbers, Next Big Sound's report covers only a certain chunk of the overall market.
Revenue recognition governs nothing less than when a company can say it has earned a certain chunk of money for a piece of contracted work.
His new place had to lie within a certain chunk of the Upper West Side — the West 60s or the low West 70s.
And, to a certain chunk of their fan base, the band's exploratory urges are what you sit through to get to the barn-burning songs like "Beautiful Day" and "Pride (In the Name of Love)" and "Vertigo".
The cultural assumptions we share with Plato and Kant are less likely to be "a tip-off to the way the world is" than just a "mark of the discourse of people inhabiting a certain chunk of space-time".
Villages can be found in plains and desert biomes, although certain chunk glitches can arise where villages are present in other biomes.
Strokes crisscross, and at a certain point chunks of flesh can fly.
When certain chunks of them got the right stamp of approval from credit rating agencies, A.I.G. was willing to insure them for even less.
Modern stylometrists can deploy programs to seek subtle patterns in how individuals tend to use language — for instance, the recourse to certain chunks of words ("word stems"), as well as clustered "n-grams" of characters, words, and parts of speech.
Still, certain chunks of the book are unlikely to appeal to casual Simpsons viewers.
