Qof

Qof is sometimes pronounced as the 'q' in 'queen' or 'quick' whereas for others, it is used as a 'k':

You will see some resources that suggest that the 'k' pronunciation is becoming increasingly common whilst others suggest exactly the opposite. The 'q' sound is however more widely accepted as the 'correct' pronunciation, so it is probably better to stick with this.

Introduction to Reading Hebrew
The first basics
The Hebrew AlephBet
The Letters of the AlephBet
Aleph
Bet (Beyt)
Gimmel
Dalet
Hey
Vav
Zayin
Chet
Tet
Yod
Kaf
Lamed
Mem
Nun
Samekh
Ayin
Pey (Fey)
Tsade (Tsadik)
Qof
Resh
Shin
Tav
The Significance of the Alephbet
The Basics of Hebrew Verbs
The Hebrew Verb Subject
The Hebrew Verb Object
Hebrew Verb Tenses
Hebrew Verb Voices and Moods
Hebrew Verb Participles
The Infinite Verb Version
Hebrew Nouns
Hebrew Noun Constructs
Using Prefixes With Nouns
Hebrew Pronouns
Hebrew Plural Nouns
Hebrew Adjectives
Identifying Hebrew Questions
Adverbs, Prepositions and Conjunctions
Hebrew Reading Conclusion