Salaah

Q: My question is about a random salafi brother that came up to me after Salah and he is like you should not have stood alone at the back your Salah is not accepted. I believe its Makrooh to stand alone in a Saaf. There was no space and later someone joined as well. I just wanted dalil for my self not for anyone else. I got very irritated because I could see he was just bringing up issue after issue. Allhumdulilah I read your fatwas everyday, he went on after that talking about where we place our hands and he was like Walahi the hadith is daaif about Ali Radhiallahu anho. I was so shocked he was taking Qasam on everything. I have read proofs from your website about the hands. My main concern is my intention. I am going to be starting Alim course soon. Could you explain the type of intention I should have when studying and coming across people like this. I know everything is for the sake of Allah. But I felt very angry towards this person more then anything and I had this feeling which was from shaitaab to prove him wrong.

Q: Is it a Sunnah after fardh Salaah to read Allaahu Akbar once and 3 times astagfirullah. The Third astagfirullah should be recited audibly and pull on laah?

Q: What is the benefit of moving from one's place after the fardh salaah before the sunnah?

Q: If one omits the Tasmiyah before Surah Fatiha in the 2nd, 3rd and 4th rakaat of Salaah due to habit, will the Salaah be acceptable? When we read Salaah with Jamaat, the Tasmiya is always silent and unfortunately I developed this habit.

Q: When performing Salaah behind the Imaam, in the sujud after saying a few times "subhana rabbiyal alaa" somehow I was about to say "sami Allahu liman hamidah" but as soon as i said "sami Al" I realisized and cutt off and continued saying "subhana rabbiyal alaa". Now was my prayed invalidated since I cutt of at the half? Must I repeat it?

Q: Where I work, sometimes it is not possible to perform complete Salaah. In Islam can we just perform fardh only when at work?

Q: Is it permissible to read Salaah in front of a mirror?

Q: My question is that can my mother complete the fardh namazes,fasts etc of her mother who had passed away (dead) so that she will be safe on the judgment day? Or there is some other way in Islam by which we can fulfil the remaining fardh ibaadaat of relatives who are no more alive?

Q: Please could you explain the method of performing qadhaa salaah missed from the time of puberty, as well as clarify the following:

1. Besides sunrise, zawaal and sunset, are there any times during which one cannot perform qadhaa salaah?
2. Should qadhaa be performed before or after adhaa salaah?
3. Is there a limit to the number of qadhaa salaah that can be performed at a time?
4. Does qadhaa have to be performed in the sequence it was missed? If I have missed a salaah today, do I make up that salaah first, or do I continue making up my previous missed salaah?
5. Any other information that you think will assist me in this regard?

Q: A person who is unable to do ruku and sajdah and is praying the complete salah sitting on a chair,what is the sunnah and correct manner of doing ruku and sajdah?