Qur'anic Verse

Are there any hadith or Quranic verses that mention the existence of 12 imams after our Prophet Muhammad (saw)? Sayyed Mohammad Al-Musawi	Why does Allah mention that humans were created in hardship (fi kabad)? Amina Inloes
In regards to Quranic verses 55:19 and 20, it mentions the creation of two seas and a barrier preventing them from mixing. However, it has been scientifically proven that they mix in minuscule amounts. How can this be explained? Sayyed Mohammad Al-Musawi	The Quran in 51:49 states that everything was created in pairs. How does this apply to asexual plants, animals, bacteria, and viruses, which only need themselves to reproduce? What is the counterpart in such scenarios? Sayyed Mohammad Al-Musawi