Wednesday Dec 16, 09 – 29 Kislev 5770
(5th Day of Chanukah, at night we light 6 candles)
1. Technically speaking, it is enough to light one single candle every night. As we say in the Berakha: lehadlik NER Chanukah (to light the candle, not candles, of Chanukah). As we all know, today our custom is to add one more candle for each night. However, in extreme cases where you cannot light all the candles, for example, if one is on a trip or in a Hotel room, etc., lighting one candle any night will be enough.
2. The candles could be made of wax, paraffin, regular oil, etc., but ideally one should use olive oil, because the miracle we are celebrating was about olive oil. Another advantage of olive oil is that normally the oil candles will last for more time, while some small wax candles will last less than the required time (half hour).
3. In the past, people used to place the Chanukkiah outside the door, on opposite side to the Mezuzah, which technically speaking is the best place for it (some families still do it!). But nowadays, the Chanukkiah is normally lit inside the house, close to a window, in a way that could be visible from outside.Recommended link to visit - On the prayer Al haNisim: http://www.ou.org/chagim/