How to transform a knowledge base (CNF) from propositional logic in a set?

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I have a proposition logic knowledge base which contains my neg query in CNF: $$\begin{split}1.~& \neg P \lor Q\\ 3.~& P \\ 4.~& R \lor S\\ 5.~& \neg R\end{split}$$

Is it possible to transfer them into set theory? Are all these syntacitally and semantically correct?

$$ K =\{(\neg P \lor Q), (P), (R \lor S), (\neg R) \}$$ $$ K =\{\{\neg P \lor Q\}, \{P\}, \{R \lor S\}, \{\neg R\} \}$$ $$ K =\{\{\neg P , Q\}, \{P\}, \{R , S\}, \{\neg R\} \}$$

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All are valid representations of a CNF, depending on the task.

The first is a set of predicates, which so happen to all be disjunctions or literals.   When the set is read conjunctively, this is a CNF.

The second is a set of clauses, several of which have terms which are disunctions rather than literals or negated literals.   This is ... not wrong, but rarely used as is.

The third is a set of clauses, each of which are sets of literals or negations of literals.   This is the preferred representation when the task is resolution.