Does passing wind, from the anus without a smell, invalidate prayer?
If a person is certain of having passed wind even if it was with no smell, then both his/her ablution and prayer are invalidated, thus he/she should remake ablution and re-perform prayer.
I have a question regarding the deferred portion of the dowry (Mahr)*. Is the wife entitled to it only upon divorce or she can claim it even if divorce hasn`t taken place? Moreover, does she have the right to claim this portion after death of husband, even if he didn`t divorce her before that?
All perfect praise be to Allah the Lord of The Worlds. May His blessings and peace be upon our Prophet Mohammad and upon all his family and companions.
In the marriage contract, it is recorded that the deferred portion of the dowry is due upon divorce or death, whatever comes first. If divorce took place first then the woman is entitled to it and if the husband died this amount must be paid from his estate. On the other hand, if the woman died then the husband becomes liable for this portion and it becomes part of the woman`s estate. We advise every husband to give this portion to his wife while alive because it is a right of hers. And Allah The Almighty Knows Best.
* In Islam, a Mahr is the obligation, in the form of money or possessions paid by the groom, to the bride at the time of Islamic marriage (payment also has circumstances on when and how to pay). While the mahr is often money, it can also be anything agreed upon by the bride such as jewelry, home goods, furniture, a dwelling or some land. Mahr is typically specified in the marriage contract signed upon marriage.
Does wiping over one's socks during ablution permissible?
If the socks were thick, then wiping over them during ablution is permissible so long as wiping conditions are observed. And Allah Knows Best.
What is the ruling on a man leading his sisters in obligatory prayer, or Taraweeh prayer (Night prayer in Ramadan)?
The prayer of the man who leads his wife, or sisters in prayer is valid, but it is more rewarding for him to offer obligatory prayer in the mosque. And Allah Knows Best.