Placing Of Right Hand On The Left Hand In Salah.

Narrated Sahl bin Sa'd:
The people were ordered to place the right hand on the left forearm in the prayer. Abu Hazim said, "I knew that the order was from the Prophet ."
Sahih Al-Bukhari (Volume 1, Book 12, Number 707)

Narrated Abdullah ibn Mas'ud:
 AbuUthman an-Nahdi said: When Ibn Mas'ud prayed he placed his left hand  on the right. The Prophet (ﷺ) saw him and placed his right hand on his  left one.
 Sunan Abi Dawud( Hadith No 755)

Narrated Tawus:
 The Messenger of Allah (ﷺ) used to place his right hand on
his left hand, then he folded them strictly on his chest in prayer.
 Sunan Abi Dawud ( Hadith No759)

Zur’ah b. ‘Abd al-Rahman said:
  I heard Ibn al-Zubair say: Setting the feet right and placing one hand on the other is a sunnah.
 Sunan Abi Dawud (Hadith No 754)

Related Hadith:

How and When to raise Hand for Takbir in salat?

Narrated Salim bin 'Abdullah:
My father said, "Allah's Apostle used to raise both his hands up to the level of his shoulders when opening the prayer; and on saying the Takbir for bowing. And on raising his head from bowing he used to do the same and then say "Sami a-l-lahu Liman hamida, Rabbana walaka-l-hamd." And he did not do that (i.e. raising his hands) in prostrations. Sahih Al-Bukhari (Volume 1, Book 12, Number 702)

Narrated Abu Qilaba:
I saw Malik bin Huwairith saying Takbir and raising both his hands (on starting the prayers and raising his hands on bowing and also on raising his head after bowing. Malik bin Huwairith said, "Allah's Apostle did the same." Sahih Al-Bukhari (Volume 1, Book 12, Number 704)

What to say in the pause between Takbir and recitation?

Narrated Abu Huraira:

Allah's Apostle used to keep silent between the Takbir and the recitation of Qur'an and that interval of silence used to be a short one. I said to the Prophet "May my parents be sacrificed for you! What do you say in the pause between Takbir and recitation?" The Prophet said, "I say, 'Allahumma, ba'id baini wa baina khatayaya kama ba'adta baina-l-mashriqi wa-l-maghrib. Allahumma, naqqim min khatayaya kama yunaqqa-ththawbu-l-abyadu mina-ddanas. Allahumma, ighsil khatayaya bil-ma'i wa-th-thalji wal-barad (O Allah! Set me apart from my sins (faults) as the East and West are set apart from each other and clean me from sins as a white garment is cleaned of dirt (after thorough washing). O Allah! Wash off my sins with water, snow and hail.)" Sahih Al-Bukhari (Volume 1, Book 12, Number 711)

Recitations of Suratul Fatiha is Compulsory in a Salah.

Allah's Apostle said, "Whoever does not recite Al-Fatiha in his prayer, his prayer is invalid." Sahih Al-Bukhari (Narrated 'Ubada bin As-Samit)

Narrated 'Abdullah bin Abi Qatada:
My father said, "The Prophet in Zuhr prayers used to recite Al-Fatiha along with two other Suras in the first two Rakat: a long one in the first Rak'a and a shorter (Sura) in the second, and at times the verses were audible. In the 'Asr prayer the Prophet used to recite Al-Fatiha and two more Suras in the first two Rakat and used to prolong the first Rak'a. And he used to prolong the first Rak'a of the Fajr prayer and shorten the second. Sahih Al-Bukhari (
Volume 1, Book 12, Number 726)

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