Clarification of those upon whom the alms given at the end of Ramadan is obligatory

The following message reached us from Quba. It was sent by our brother Saleh Abdullah from the municipality of Quba. Our brother has a number of questions, among which is one that says: List for us all those upon whom the alms given at the end of Ramadan is obligatory and those upon whom it is not obligatory, what is its amount, and is it permissible to give its value?
Answer: The alms given at the end of Ramadan is obligatory upon every Muslim, young or old, if he is present when the sun sets on the night of the festival at the end of Ramadan. The Prophet (peace and blessings be upon him) made the alms given at the end of Ramadan obligatory upon the young and the old, the male and the female, the free and the slave among the Muslims. He ordered that it be performed before the people go out to the prayer, meaning: to the festival prayer. This is what is obligatory upon those whom the Prophet (peace and blessings be upon him) mentioned: the males and females, the young and the old, the free and the slaves among the Muslims.
As for the fetus in the womb of a woman at the time of the festival, the alms given at the end of Ramadan is not obligatory upon it, but it is recommended; because 'Umar ibn al-Khattab (may Allah be pleased with him), the righteous caliph, gave it on behalf of the fetus, so the scholars recommended it following 'Umar (may Allah be pleased with him).
Likewise, it is not obligatory upon the disbeliever or the disbeliever woman; because they are not among the people of purity and they are not among the people of alms until they submit to Islam. So if a disbeliever has a disbelieving slave or a disbelieving child, he does not give alms on their behalf; because he is impure by disbelief, and alms does not purify him. So there is no alms except upon the Muslim. Yes.