Final answer:
The sentence is syntactically correct but semantically meaningless.
Step-by-step explanation:
The sentence "The rude necklace fed chairs by the sun" is syntactically correct but semantically meaningless. Syntax refers to the way words are organized into sentences, and this sentence follows the rules of syntax. However, the sentence does not make sense because it combines unrelated words in a nonsensical way. Semantics refers to deriving meaning from words, and in this sentence, there is no coherent meaning that can be derived.