While the spelling only differs in the ‘k’…

Answer
Both words are borrowed from French, which explains the pronunciation. Of course, the words could also have been written, as in French, making the spelling closer to pronunciation.
Apparently, the spelling has gone back to the Latin origin of these words: in Latin both variants are written with a
The spelling of a language is never completely phonetic, nor is it possible. Other considerations come into play when devising the spelling of a language. In this case, Dutch takes into account the Latin origin of the word and reflects that origin (etymology) in the script.
Answered by
Prof. Eugeen Roegiest
Linguistics of the Romance languages ​​and Spanish in particular
http://www.ugent.be
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