The word(s) "painful" appears 75 time(s) in 75 verse(s) in Quran in Mohsin Khan translation.

(51) Verily, you (pagans of Makkah) are going to taste the painful torment;

(52) The Day when their excuses will be of no profit to Zalimun (polytheists, wrong-doers and disbelievers in the Oneness of Allah). Theirs will be the curse, and theirs will be the evil abode (i.e. painful torment in Hell-fire).

(53) Nothing is said to you (O Muhammad صلى الله عليه وسلم) except what was said to the Messengers before you. Verily, your Lord is the Possessor of Forgiveness, and (also) the Possessor of painful Punishment.

(54) Or have they partners with Allah (false gods) who have instituted for them a religion which Allah has not ordained? And had it not been for a decisive Word (gone forth already), the matter would have been judged between them. And verily, for the Zalimun (polytheists and wrong-doers) there is a painful torment.

(55) The way (of blame) is only against those who oppress men and rebel in the earth without justification; for such there will be a painful torment.

(56) But the sects from among themselves differed. So woe to those who do wrong [by ascribing things to 'Îsa (Jesus) that are not true] from the torment of a painful Day (i.e. the Day of Resurrection)!

(57) Covering the people: this is a painful torment.

(58) Who hears the Verses of Allah (being) recited to him, yet persists with pride as if he heard them not. So announce to him a painful torment!

(59) This (Qur'an) is a guidance. And those who disbelieve in the Ayat (proofs, evidence, verses, lessons, signs, revelations) of their Lord, for them there is a painful torment of Rijz (a severe kind of punishment).

(60) Then, when they saw it as a dense cloud coming towards their valleys, they said: "This is a cloud bringing us rain!" Nay, but it is that (torment) which you were asking to be hastened - a wind wherein is a painful torment!